Error occurring in specific API versions

When I create a new project

AndIchoosetheminimumSDK10

It creates the Android package with main.java and activy_main.xml (and other things) only when it compiles the codes of those errors and I do not know why. I tested up API 16 and ran the min SDK without this error. APIs 10, 8, and 7 when you create the project give this error:

SDKSTOOLSANDEXTRASTHATICAN(ALLINSTALLEDBYTHESDKMANAGER)

FinishinginstallingAPI15

Build.grad(APP)

applyplugin:'com.android.application'

android{    compileSdkVersion20    buildToolsVersion"21.1.1"

defaultConfig {
    applicationId "com.guga.myapplication"
    minSdkVersion 10
    targetSdkVersion 20
    versionCode 1
    versionName "1.0"
}
buildTypes {
    release {
        runProguard false
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
    }
}

}

dependencies {     compile fileTree (dir: 'libs', include: ['* .jar'])     compile 'com.android.support:appcompat-v7:21.0.2' }

Build.gradle ("Application Name")

// Top-level build file where you can add configuration options common to all sub-projects / modules.

buildscript {     repositories {         jcenter ()     }     dependencies {         classpath 'com.android.tools.build:gradle:0.13.2'

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

}

allprojects {     repositories {         jcenter ()     } }