A test contains 10 questions and each question has 4 options to answer in with 1 being the correct answer.I'm completely stranded in probability. I'm trying to get it in the P and C formats but it won't work. Help is very much appreciated.

What is the probability of gettingat least4 questions right if answers are randomly selected?

What is the probability of getting between 2 to 7 questions right (3,4,5,6) if answers are randomly selected?