What are the common multiples of 2,5 and 10?

this is worth 55 points, so answer wisely!

Suppose a ball is dropped fromca height of 6ft. it bounces back up but time it bounces, it reaches only 7/10 of its pervious height. what is the total of each height that the ball reaches after 5 bounces

Plzz ! if you were constructing a triangular frame, and you had wood in the length of 4 inches, 4 inches, and 7 inches, would it make a triangle? would you be able to create a frame from these pieces of wood? yes or no? = explain your mathematical thinking/show your work:

Ineed with question three. i don't understand how i'm supposed to achieve 3 marks.