9. Post Malone opened up for __ on the Purpose World Tour. (10 Points Brittney Spears Usher Justin Bieber Rhianna

## Step 1<br />This problem is a factual question about a specific event in the music industry. It asks who Post Malone opened up for on the Purpose World Tour. The options provided are Brittney Spears, Usher, Justin Bieber, and Rihanna.<br />## Step 2<br />To solve this problem, we need to know the correct information about the Purpose World Tour. According to the information provided, Post Malone opened up for Justin Bieber on the Purpose World Tour.