Build an Android app with Jetpack Compose and Firebase

1. Each page of an Android app that's built with Jetpack Compose and follows the Model-View-ViewModel (MVVM) architecture should include which of the following?

   A Screen file with a composable function that declares how the UI should look and a ViewModel class that performs the business logic.

   A Screen file with a composable function that declares how the UI should look and a Service file that calls Firebase APIs.

   A Screen file with a composable function that declares how the UI should look, a ViewModel class that performs the business logic, and a Service file that calls Firebase APIs.

   None of the above.

2. Kotlin coroutines are which of the following?

   Data streams that emit sequential values as a way to exchange information between the different layers of your app.

   Lightweight threads that let you write synchronous code.

   Lightweight threads that let you write asynchronous code.

   All of the above.

3. How do you differentiate a regular Kotlin function from a composable function?

   The composable function has an @ComposableFunction annotation.

   The composable function is usually wrapped in a Composable class.

   The composable function has an @Composable annotation.

   The composable function always returns a composable.

4. How do you ensure that composable functions stay aware of updated documents stored in Cloud Firestore?

   Add a SnapshotListener object to the Cloud Firestore collection in your data layer, and then update the UI state in the ViewModel class and observe this UI state in the composable function.

   Add a SnapshotListener object to the Cloud Firestore collection at the beginning of your composable function and then update the screen accordingly.

   Add a SnapshotListener object to the Cloud Firestore collection in your data layer, and then apply the business logic to the composable function and update the screen accordingly.

   Add a SnapshotListener object to the Cloud Firestore collection in your ViewModel class and then call your composable function from the ViewModel class on each update.

5. Firebase Performance Monitoring lets you do which of the following?

   Choose as many answers as you see fit.

   Automatically capture traces when you add the SDK.

   Create custom traces, metrics, and attributes for specific code.

   Configure your dashboard with important traces.

   Permanently store personally identifiable information.

6. How do you monitor performance data associated with specific code in your app?

   Add a custom metric that starts at the beginning of the specific code and ends after this code runs.

   Add a custom trace that starts at the beginning of the specific code and ends after this code runs.

   Add the @CustomTrace annotation to the function that you want to monitor.

   Add the @CustomMetric annotation to the function that you want to monitor.

7. True or false? You can use Firebase Remote Config to introduce features to a percentage of your users so that you can measure their impact before you release them to your entire user base.

   True

   False

8. Which of the following Remote Config API methods is mandatory and should you call as soon as the app starts?

   The get() method to fetch the value for the key that you want. You should call it once for every key.

   The setMinimumFetchIntervalInSeconds() method to configure the minimum interval in which the app can ask for new values.

   The getAll() method to fetch all the pairs of keys and values available.

   The fetchAndActivate() method to fetch all values and activate them.

9. What's the best way to fix a customer issue in your app?

   Fix the code and release a new version directly to production.

   Fix the code and manually verify it in the production environment.

   Fix the code and manually verify it in a preproduction environment.

   Fix the code, then manually verify it in a preproduction environment, and finally write an integration test to prevent a future regression.

10. To identify the production environment in the Firebase console, you should look for which of the following icons?

    Red rocket

    Green check mark

    Blue circle with an arrow

    Gold star

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