having trouble with this one

63% of owned dogs in the United States are spayed or neutered. Round your answers to four decimal places. If 33 owned dogs are randomly selected, find the probability that a. Exactly 21 of them are spayed or neutered. b. At most 21 of them are spayed or neutered. C. At least 19 of them are spayed or neutered. d. Between 20 and 25 (including 20 and 25) of them are spayed or neutered