Which value does the "Width" property require?

The Windows Phone Analysis tool can do which of the following?

Which is a popular design pattern for building Windows Phone applications?

You cannot run a Windows Phone 8 app on a Windows Phone OS 7.1.

Which is benefit of using native code?

What is XAP?

If an app performs an operation that causes the device to appear to be unresponsive for more than three seconds, such as downloading data over a network connection, the app must display a visual progress or busy indicator.

Which shoud be considered when developing an app to run on lower-memory devices?

Which is part of Window Phone Developer Tools?

MainPage.xaml.cs and MainPage.xaml.vb contain the code to handle _____.

Which is NOT released WindowsPhone OS system versions?