The guidance system for a rocket operates correctly with probability p when called upon. Independently but identical buckup systems are installed in the rocket so that the probability that at least one system will operate correctly when called upon is no less than 0.99. Let n denote the number of guidance systems in the rocket. How large must n be to achieve the specific probability of at least one guidance system operating if: a. p=0.9 and b. p=0.8