Can someone me with this question?

Tyler enjoys the fish so much that after his birthday his family decides to take him to a famous aquarium a tank at the aquarium is similar to his tank with the scale factor of 8 how many times greater is the volume of the tank at the aquarium than the volume of tyler tank

Which word in the sentence below is an interrogative pronoun? who is picking us up from school? whousisfrom

Using only the digits 5, 6, 7, 8, how many different three digit numbers can be formed if no digit is repeated in a number?