앱 테스트 구동이 안돼요

BTS 강의 레이아웃에 사진삽입 6분 4초쯤 보고 있는데요,

알려주신대로 다음과 같이 코드를 입력하고 앱 구동을 눌렀는데

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="120dp">

        <ImageView
            android:src="@drawable/bts_1"
            android:layout_width="120dp"
            android:layout_height="120dp">

        <ImageView
            android:src="@drawable/bts_2"
            android:layout_width="120dp"
            android:layout_height="120dp">

        <ImageView
            android:src="@drawable/bts_3"
            android:layout_width="120dp"
            android:layout_height="120dp">

    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="120dp">

        <ImageView
            android:src="@drawable/bts_4"
            android:layout_width="120dp"
            android:layout_height="120dp">

        <ImageView
            android:src="@drawable/bts_5"
            android:layout_width="120dp"
            android:layout_height="120dp">

        <ImageView
            android:src="@drawable/bts_6"
            android:layout_width="120dp"
            android:layout_height="120dp">

    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="120dp">

        <ImageView
            android:src="@drawable/bts_7"
            android:layout_width="120dp"
            android:layout_height="120dp">

    </LinearLayout>

</LinearLayout>

다음 문구와 같이 에러가 떠서 테스트 구동이 안됩니다.

Caused by: org.gradle.workers.internal.DefaultWorkerExecutor$WorkExecutionException: A failure occurred while executing com.android.build.gradle.internal.res.ParseLibraryResourcesTask$ParseResourcesRunnable

뭐가 잘못된건가요??