Failed to resolve Junit:Junit:12

Question

I am getting following error when I tried to run my first app in android studio

Error:A problem occurred configuring project ':app'.
> Could not resolve all dependencies for configuration ':app:_debugUnitTestCompile'.
   > Could not resolve junit:junit:4.12.
     Required by:
         Hellow_World:app:unspecified
      > Could not resolve junit:junit:4.12.
         > Could not get resource 'https://jcenter.bintray.com/junit/junit/4.12/junit-4.12.pom'.
            > Could not GET 'https://jcenter.bintray.com/junit/junit/4.12/junit-4.12.pom'.
               > jcenter.bintray.com

Following is my Gradle.script(Module)

apply plugin: 'com.android.application'

android {
    compileSdkVersion 23
    buildToolsVersion "23.0.3"

    defaultConfig {
        applicationId "com.example.administrator.hellow_world"
        minSdkVersion 15
        targetSdkVersion 23
        versionCode 1
        versionName "1.0"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    testCompile 'junit:junit:4.12'
    compile 'com.android.support:appcompat-v7:23.3.0'
}

Following is my Gradle.script(Hellow_World)

buildscript {
    repositories {
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:2.1.0'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        jcenter()
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

Can somebody help me fixing this mess?