A professor has learned that four students in her class of 18 will cheat on the exam. She decides to focus her attention on sevenrandomly chosen students during the exam.a. What is the probability that she finds at least one of the students cheating? (Round your final answers to 4 decimal places.)Probabilityb. What is the probability that she finds at least one of the students cheating if she focuses on eight randomly chosen students?(Round your final answers to 4 decimal places.)Probability