INF-306 HTML5 Application Development Question and Answers

The correct element is animateTransform. In SVG, rotation is not produced by drawing a different shape; it is produced by applying a transformation to an existing graphical element, such as a < rect > representing a square. The < animateTransform > element is specifically designed to animate the transform attribute of a target SVG element, and its supported transformation types include translation, scaling, rotation, and skewing. Therefore, to rotate a square, the square would normally be defined with a shape element such as < rect > , and an < animateTransform > child or associated animation would specify attributeName= " transform " and type= " rotate " . animateMotion is incorrect because it moves an element along a motion path rather than rotating the element itself. circle is a shape element, not an animation mechanism. path defines arbitrary vector geometry, but it does not by itself animate or rotate another object. References/topics: SVG graphics, SVG transformations, animation elements, transform attribute, rotation animation.

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@media screen and (max-width: 480px) {

/* style rules go here */

}

The correct media query is @media screen and (max-width: 480px) {. The requirement says the style rule must apply to screen devices with a width of 480 pixels or less. In CSS media queries, screen identifies the media type, and (max-width: 480px) defines the upper viewport-width limit. This means the enclosed CSS rules apply when the viewport is 480 pixels wide or any smaller value, which is the standard mobile breakpoint behavior. @media screen and (width: 480px) is incorrect because it applies only when the viewport is exactly 480 pixels wide, not below it. @media screen display and (width: 480px) is invalid syntax because display is not used that way in a media query. @media screen-width: 480px is also invalid because it does not follow the required @media media-type and (feature: value) pattern. References/topics: responsive design, CSS media queries, @media, screen media type, max-width, mobile breakpoint styling.

display: grid;

grid-template-columns: repeat(6, 1fr);

grid-template-rows: 50px 50px 150px 150px 100px;

grid-gap: 10px 15px;

The correct grid definition starts with display: grid;, which turns the element into a CSS Grid container. To explicitly create six equal-width columns, the correct property is grid-template-columns, and the most efficient value is repeat(6, 1fr). The repeat() function avoids writing 1fr six separate times, while 1fr assigns each column one equal fraction of the available grid width. The five row sizes must be explicitly declared with grid-template-rows, using the exact varied values shown: 50px 50px 150px 150px 100px. This creates five rows with fixed pixel heights. For the spacing requirement, grid-gap: 10px 15px; is the correct shorthand. The first value controls the row gap, so rows are separated by 10px; the second value controls the column gap, so columns are separated by 15px. References/topics: CSS Grid containers, explicit grid tracks, grid-template-columns, grid-template-rows, repeat(), fractional units, grid gaps.

A CSS flexible box layout is created by applying the display property to a container with either flex or inline-flex. This establishes the element as a flex container and causes its child elements to become flex items. The flex-direction property defines the direction of the main axis and accepts row, row-reverse, column, and column-reverse, allowing items to flow horizontally, vertically, or in reverse order. The align-items property controls how flex items are aligned along the cross axis, with values such as flex-start, flex-end, and center. The direction property controls writing direction and accepts ltr for left-to-right text flow or rtl for right-to-left text flow. Finally, order is applied to individual flex items and accepts an integer value, represented here as “any,” because any numeric order value can be used to rearrange item display order without changing the document source order. References/topics: CSS flexbox, flex containers, flex items, main axis, cross-axis alignment, writing direction, item ordering.

First blank: img

Second blank: filter:

Third blank: grayscale(100%)

Fourth blank: blur(8px)

The correct CSS selector is img because the requirement applies the visual effect to gallery images. The correct property is filter:, not transform:, because CSS filters modify the rendered appearance of an element using image-processing effects such as blur, grayscale, opacity, brightness, contrast, and shadows. The filtered sample appears blurred and colorless, so the appropriate filter functions are grayscale(100%) and blur(8px). grayscale(100%) removes all color from the image, converting it to a black-and-white rendering. blur(8px) obscures visual details, making the image difficult to recognize until the protected or authorized state changes the styling. The filter keyword without a colon is not a valid CSS declaration in this context. brightness(40%) and opacity(50%) could further obscure an image, but they are not required to reproduce the shown filtered result. The final declaration is therefore filter: grayscale(100%) blur(8px);.

The correct selections are B and C because both define a function as a member of an object context, which is the essential JavaScript pattern for declaring a method. MDN defines a method as a function that is a property of an object. It also shows that a function expression can be assigned to a variable or property and then invoked later. In option B, Score: function() { ... } represents an object-literal method property. This pattern is commonly used when defining custom objects, prototypes, configuration objects, or class-like structures in JavaScript. In option C, this.Score = function() { ... } assigns a function to the current object instance, creating an instance method that can be called through that object. Option A does not declare a method; as written, it is only an invalid or incomplete variable assignment and does not use the function keyword or method syntax. Option D invokes Score() and assigns its return value to a; it calls a function rather than declaring a method. References/topics: JavaScript custom classes, object members, function expressions, object-literal methods, instance methods.

The correct coordinate is 50,50. In an HTML5 canvas, the coordinate system begins at the upper-left corner of the canvas. The x-coordinate increases as you move to the right, and the y-coordinate increases as you move downward. Therefore, 0,0 represents the top-left corner of the entire white canvas area. In the displayed image, the filled black square is not positioned at the top-left edge, top-center, or left-center of the canvas. Instead, its upper-left corner is offset both horizontally and vertically from the origin. Among the available choices, 50,50 is the only coordinate that moves the square 50 units to the right and 50 units down from the canvas origin. This matches the visual placement of the filled square inside the white canvas. Option A would place the square at the canvas origin. Option B would place it along the left side, halfway down. Option C would place it along the top edge, halfway across. References/topics: HTML5 canvas coordinate system, x/y positioning, drawing rectangles, fillRect(x, y, width, height).

First blank: < svg width= " 200 " height= " 200 " >

Second blank: < rect width= " 200 " height= " 200 "

Third blank: < circle cx= " 100 " cy= " 100 " r= " 50 "

Fourth blank: < /svg >

The correct solution uses SVG because SVG graphics are vector-based and can scale without pixel distortion when the page or viewport changes. A < canvas > element would require script-based drawing logic, which violates the requirement that JavaScript must not be required. An < img > or < picture > element can display an image, but those options do not define the rectangle and circle directly in markup. The outer container must therefore be < svg width= " 200 " height= " 200 " > . The blue square is created with < rect width= " 200 " height= " 200 " fill= " blue " / > , which produces a rectangle matching the required 200-by-200 dimensions. The centered white circle must use SVG circle geometry: cx= " 100 " and cy= " 100 " place the center at the midpoint of the 200-by-200 square, and r= " 50 " creates the required 50-pixel radius. The final closing tag must be < /svg > .

The correct answer is A because the code at line 03 creates an object by calling a constructor function with the new keyword. A constructor function must be declared with the same identifier used in the new Student( " David " , " Hamilton " ) expression. Inside the constructor, instance members should be assigned through this, because this refers to the newly created object. Option A correctly initializes this.firstname, this.lastname, and this.fullname, so beststudent.fullname is available at line 04 and evaluates to " David Hamilton " . Option B is invalid JavaScript syntax because var student(firstName, lastName) is not a valid function declaration. Option C is also invalid syntax for the same reason: var Student(firstname, lastname) cannot declare a constructor. Option D uses a valid function declaration, but it assigns firstname, lastname, and fullname without this, which creates or references non-encapsulated variables rather than properties of the constructed object. References/topics: JavaScript constructor functions, new keyword, object instance properties, this, custom classes.

The correct transformation functions are matrix() and skew(). CSS transformations are applied with the transform property and accept transform functions that alter an element’s rendered appearance in two-dimensional or three-dimensional space. MDN defines < transform-function > as a data type representing a transformation that can rotate, resize, distort, or move an element in 2D or 3D space. The matrix() function is valid because it defines a homogeneous two-dimensional transformation matrix, allowing translation, scaling, rotation, and skewing effects to be represented numerically in one function. The skew() function is also valid because it explicitly skews an element on the 2D plane. scroll() is not a CSS transform function; scrolling is handled through overflow behavior or scrolling APIs. move() is also not a valid CSS transform function; the standard transform function for movement is translate(). References/topics: CSS3 transforms, transform property, 2D transformation functions, matrix(), skew().

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The correct segment is D because named grid-region layouts are defined with grid-template-areas. This CSS Grid property specifies named grid areas, establishes the cells in the grid, and assigns names to those cells. The syntax requires each row of the grid template to be written as a quoted string, with repeated names indicating that the named area spans multiple columns or rows. In the shown layout, heading spans the entire top row, menu occupies the left column across lower rows, content spans the central area, right occupies the right-side area, and contact spans the bottom content region. Options B and C are incorrect because named grid-area strings do not belong in grid-template-rows or grid-template-columns; those properties define track sizing, not named layout regions. Option A defines explicit column and row sizes but does not define the semantic named areas shown in the mockup. References/topics: CSS Grid, grid containers, named grid areas, grid-template-areas, responsive page layout.

First drop-down: datalist

Second drop-down: vehicles

Third drop-down: < /datalist >

The correct element is < datalist > because the interface requires a text input that provides selectable suggestions while still allowing the user to type. The < input > element uses list= " vehicles " , so it must be connected to a < datalist > element whose id is exactly vehicles. The id cannot be vehicle, because vehicle is already the input element’s own identifier and does not match the value used by the list attribute. The < option > elements inside the datalist define the suggested values: Motorcycle, Truck, Boat, Car, and Bicycle. ul, ol, and li are list-markup elements and do not create input suggestions. select would create a fixed dropdown list, but it would not match the editable input-with-suggestions behavior shown. The closing tag must match the opening datalist element, so the final selection is < /datalist > .

The correct method is preventDefault(). During form submission, the browser’s default behavior is to submit the form to the target URL, which may navigate away from the current page or reload it. If the submitted data is invalid and the application must display custom error messages while preserving the entered values, the submit event handler should call event.preventDefault(). This cancels the default submit action, allowing the page to remain in place and the script to display validation feedback next to the relevant form controls. defaultPrevented is not the method to use; it is only a Boolean property that indicates whether preventDefault() has already been called. cancelable is also only informational; it tells whether the event’s default behavior can be canceled. abort is unrelated to form validation and does not provide the required control over form submission. References/topics: HTML5 form validation, custom validation messages, submit event, event cancellation, preserving form data.

The two likely causes are undersized touch targets and overlapping input regions. Touch input is less spatially precise than mouse input because the contact area of a finger is larger and less exact than a pointer cursor. Microsoft’s touch-target guidance states that interactive UI elements must be large enough for users to access accurately, and recommends a target size around 7.5 mm square, approximately 40 × 40 pixels on a 135 PPI display. Earlier Microsoft touch-design guidance similarly emphasizes that controls must be appropriately sized for touch and identifies approximately 9 mm as a minimum targeting area. Therefore, small input buttons may fail to trigger because the user is not actually hitting the active target area. Overlap is also a valid cause: when two active regions occupy the same physical screen area, hit testing may route the touch to a different element, or the effective target area may be reduced. W3C accessibility guidance explicitly treats overlapping targets as reducing measurable target size unless the overlapping controls perform the same action. Event handlers themselves are not the defect; they are the normal mechanism for processing input. “Touch screen not initialized” is not a standard HTML5 application cause. References/topics: touch input, event handling, hit testing, target size, overlapping controls.

pattern → Provides a way to set a regular expression that the value must match

placeholder → Provides a way to set default text that displays until focus is placed in an element

required → Provides a way to set form elements as mandatory

multiple → Provides a way to allow more than one file or email address in a single input

The correct matches are based on standard HTML5 form validation and input-attribute behavior. The pattern attribute defines a regular expression that the input value must satisfy before the form can be submitted successfully. It is commonly used for structured values such as phone numbers, codes, postal formats, or custom identifiers. The placeholder attribute supplies short hint text inside an input field, helping the user understand the expected value before entering data. The required attribute makes a form control mandatory; if the field is empty, constraint validation prevents successful submission. The multiple attribute allows a single input to accept more than one value, specifically for controls such as input type= " file " and input type= " email " , where users may upload multiple files or enter multiple email addresses. The maxlength attribute is not used in these matches because it limits the maximum number of characters that can be entered, but none of the listed descriptions asks for character-length restriction. References/topics: HTML5 form attributes, constraint validation, pattern, placeholder, required, multiple, input validation.

The valid filter declarations are filter: opacity(25%) and filter: drop-shadow(16px 16px 16px red). The CSS filter property applies graphical effects to an element, commonly including image rendering effects such as blur, contrast, color shifts, transparency, and shadows. opacity(25%) is a valid filter function because filter opacity accepts a percentage or number to control the rendered transparency of the element. drop-shadow(16px 16px 16px red) is also valid because drop-shadow() is a CSS filter function, and MDN shows that it accepts two or three length values plus an optional color. box-shadow(...) is invalid in this context because box-shadow is a standalone CSS property, not a filter function; MDN explicitly distinguishes drop-shadow() from the box-shadow property. blur(25deg) is invalid because blur uses a length value such as pixels, not an angular value such as degrees. References/topics: CSS filter property, image effects, opacity filter, drop-shadow filter, valid filter-function syntax.

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The correct answer is A. Applying float: right to an image removes the image from the normal inline flow and moves it to the right side of its containing block. Inline content, such as text, is then allowed to flow around the floated image. Because the image is anchored on the right, available text space is primarily on the left side of the image, and the text can continue above, beside, and below the floated region according to the surrounding layout. This is the classic use case for floating images within article-style content, where text wraps around a visual element rather than forcing the image to occupy an entire line. Option B is incomplete because it omits the important left-side wrapping behavior. Option C describes the opposite direction: an image floated left with text appearing to its right. Option D also describes float: left, not float: right. References/topics: CSS float, floated images, text wrapping, normal flow, content positioning.

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