title: Failed to resolve: firebase-auth-15.0.0
body: <p>Hello fellow developer i'm new to Android Development I just want to know how to resolve this kind of problem because i need to connect my app to firebase.</p>
  
  <pre><code>    apply plugin: 'com.android.application'
      apply plugin: 'com.google.gms.google-services'
  
      android {
  compileSdkVersion 28
  defaultConfig {
      applicationId "com.acemergencyapp.user.aceapp"
      minSdkVersion 14
      targetSdkVersion 28
      versionCode 1
      versionName "1.0"
      testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
  }
  buildTypes {
      release {
          minifyEnabled false
          proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
      }
  }
      }
  
      dependencies {
  implementation fileTree(dir: 'libs', include: ['*.jar'])
  implementation 'com.android.support:appcompat-v7:28.0.0'
  implementation 'com.android.support.constraint:constraint-layout:1.1.3'
  implementation 'com.google.firebase:firebase-core:16.0.3'
  implementation 'com.google.firebase:firebase-auth:16.0.3'
  testImplementation 'junit:junit:4.12'
  androidTestImplementation 'com.android.support.test:runner:1.0.2'
  androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
  implementation 'com.google.firebase:firebase-auth:16.0.1:15.0.0'
    }
  </code></pre>
  
  <p>I have a red line in <code>implementation 'com.android.support:appcompat-v7:28.0.0'</code></p>