How can you tell when a quadratic equation has two identical, rational solutions?

a) when the radicand is negative
b)when b in the quadratic formula is greater than the radicand
c)when the radicand equals zero
d)when the radicand is not a perfect square

Consider a bag that contains 220 coins of which 6 are rare indian pennies. for the given pair of events a and b, complete parts (a) and (b) below. a: when one of the 220 coins is randomly selected, it is one of the 6 indian pennies. b: when another one of the 220 coins is randomly selected (with replacement), it is also one of the 6 indian pennies. a. determine whether events a and b are independent or dependent. b. find p(a and b), the probability that events a and b both occur.