Most people DO NOT answer all 50 questions in 12 minutes. In fact, only 1% of the population answers more than 40 questions correctly in the allotted time.
You should aim to answer as many questions as you can. This means taking a guess even if you’re not sure of the answer, and especially when you feel like you’re stuck. You can always go back to earlier questions, so try to first move forward and solve questions you feel confident with.