someone help write my assignment

In a survey of 900 college students , 405 out of 900 students has credit card or 45% of the student owned a credit card.
a. In a sample of five students, what is the probability that two will have their own credit card?

b. In the sample of six students, what is the probability that at least two will have their own credit card?

c. In the sample of 10 students, what is the probability that at none will have their own credit card?