Pinterest Machine Learning Research Engineer interview questions

Applied through the website, got sent OA link on CodeSignal, didn't make it to the interviews. OA is 70 minutes for 10 questions, which is by a large margin not enough time to solve everything. It is fully proctored, i.e. they record your webcam and microphone, and you are supposed to be alone in the room - I don't think it was disclosed or obvious to me before I started the test. The test has 6 MCQs, 1 leetcode style problem, 2 "ml" problems, and 1 output-only problem. The "ml" problems are in the same style as ML homework in a college course - you're given code stubs and equations for missing parts, and you're expected to implement the missing parts. One of the silliest things in those assignments is that you're not allowed/supposed to use numpy. Weirdly enough, for those, you still can get TimeLimit exceeded on the Codesignal platform. The MCQs are super vague and unclear - despite being very knowledgeable in core ML, I wasn't sure if I answered those questions correctly.