I need the answer please for a and b

Two friends are reading books. jimmy reads a book with 21,356 words. his friend bob reads a book with one-and-a-half times as many words. which expression represents the number of words bob reads?

How many 3/8s are in 6 plz someone tell me now

Which expression equals 9^3 sqrt 10 a. 5 sqrt 10 + 4 sqrt 10 b. 5^3 sqrt 10 + 4 ^3 sqrt 10 c. 5 sqrt 10 + 4^3 sqrt 10 d. 5^3 sqrt 10 + 4 sqrt 10