(1/15) Which statement about updating a reactive array with standard JavaScript array methods in Vue 3 is true?

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• Only computed properties respond to array changes
• push, splice, shift, etc. are all tracked in Vue 3 due to proxy-based reactivity
• You must replace the entire array reference each time to trigger reactivity
• Arrays are not reactive in Vue 3

(2/15) In Vue 3, which file can you typically edit to add global CSS styles (e.g., resetting or main theme) without scoping them to any component?

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• index.html directly with <link> tags only
• router.js
• A dedicated main.css or styles.css imported in main.js
• App.vue <style scoped>

(3/15) What is the typical difference in how watch() vs. computed() handle reactivity in Vue 3?

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• watch() is for side effects when data changes; computed() is for deriving new reactive values used in templates
• watch() forcibly caches results, computed does not
• computed() always triggers watchers, watch() does not
• They are identical in usage and performance

(4/15) What happens to watchers created with watch() in Vue 3 if the component is unmounted?

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• They continue running in the background
• They persist until the user refreshes the browser
• They automatically stop when the component unmounts
• They throw an error in the console

(5/15) Which lifecycle hook in the Composition API triggers after the component is destroyed and removed from the DOM in Vue 3?

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• onDeactivated
• onErrorCaptured
• onUnmounted
• onBeforeUnmount

(6/15) In Vue 3, which built-in directive might you use if you need to render a list of items from an array or object?

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• v-for
• v-if
• v-html
• v-bind

(7/15) What is the role of defineEmits() in a Vue 3 <script setup> block?

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• It merges watchers with props
• It is only for v-for usage
• To define watchers for each prop
• To specify which events a component can emit, possibly with type definitions in TS

(8/15) If you want to manually stop collecting dependencies for a certain reactive effect in Vue 3, which function might you call?

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• stop(effect)
• cancelWatcher(effect)
• pauseEffect()
• unwatchEffect()

(9/15) How do you define watchers in a Vue 3 Options API component if you only want them to run after the component is first mounted?

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• Impossible to watch after mount in Options API
• Use defineProps for concurrency watchers
• Use watchers in main.js for concurrency watchers
• Define watchers with immediate: false (the default), so they don’t run on creation, only on subsequent changes

(10/15) Why might you choose to use computed properties over methods in a Vue 3 component?

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• Computed properties can automatically cache their results based on reactive dependencies
• Computed properties can’t be cached, while methods are cached
• Methods cannot reference reactive data
• Methods are not available in Vue 3

(11/15) What is a common use case for the 'mounted' hook in Vue 3?

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• To unmount the component
• To perform DOM-dependent operations after the component is inserted
• To set initial data properties
• To define watchers for reactive properties

(12/15) Which directive might you use if you want to render a block for each item in an array in Vue 3, referencing item.key as the unique key?

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• v-if
• v-model
• v-for
• v-bind

(13/15) Which directive can you use to dynamically bind a boolean HTML attribute (e.g., disabled) in a Vue 3 template?

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• v-on
• v-if
• v-model
• v-bind

(14/15) In Vue 3, how do you dynamically apply multiple styles to an element based on component data?

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• Use watchers that manipulate the DOM styles manually
• Only a single style can be bound at one time
• Use v-bind:style with an object or an array of style objects
• Apply the 'scoped' attribute in the <style> block

(15/15) Which directive in Vue 3 do you use if you want to bind multiple classes conditionally at once, for instance: :class="{ active: isActive, hidden: isHidden }"?

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• v-class="[active, hidden]"
• v-on:class
• v-bind:class or :class
• v-model:class

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