Android Studio中的Firebase出现错误

我在Android Studio中的Firebase出现了这个错误，我不知道如何修复它。你能帮我吗

以下是错误：

Executing tasks: [:app:generateDebugSources, :app:generateDebugAndroidTestSources, :app:mockableAndroidJar, :app:prepareDebugUnitTestDependencies]

Configuration on demand is an incubating feature.
NDK is missing a "platforms" directory.
If you are using NDK, verify the ndk.dir is set to a valid NDK directory.  It is currently set to C:\Users\kites\AppData\Local\Android\Sdk\ndk-bundle.
If you are not using NDK, unset the NDK variable from ANDROID_NDK_HOME or local.properties to remove this warning.

google-services plugin could not detect any version for com.google.android.gms or com.google.firebase, default version: 9.0.0 will be used.
please apply google-services plugin at the bottom of the build file.
Incremental java compilation is an incubating feature.
FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:processDebugGoogleServices'.
> File google-services.json is missing. The Google Services Plugin cannot function without it. 
   Searched Location: 
  C:\Users\kites\AndroidStudioProjects\60degree\app\src\debug\google-services.json
  C:\Users\kites\AndroidStudioProjects\60degree\app\google-services.json

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.

BUILD FAILED

Total time: 4.148 secs

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文件google-services.json丢失

。。。请从头开始再次阅读文档Google-services.json信息可在此处找到：