Where to find the sample problems in the videos on the 2-month study plan?

Hey everybody, I am on the Week 1, Day 1 section and watching the “Integers and Primes” video that is linked. In his video, Greg pulls up sample problems where he is working through the questions with the students. My question is, where do I find these problems, is he pulling them from another resource?

Thanks!

Yes, probably from ETS or GMAT books.