For number 1, add the sides of the triangle. They are all given. The answer is 19.
For number 2, you use the formula for circumference, 2 times pi times radius. The answer is 43.96.
For number 3, I assume that 5 is half of one side. You would double 5 to get ten and multiply it by four, since there are four sides in a square. The answer is 40.
For number 4, you would multiply 5 times pi, but don't solve it. ( since the directions are to leave the answer in terms of pi) The answer is 5 pi.
For number 5, add all the sides together like number 1. The answer is 18.
#2. 43.96 #4. 15.7 I'm not sure about the rest of them but I am good with circles. For #2. do 3.14 times 14 because the radius is 7 and the diameter is 14. Then for number 4 you do the same thing but multiply by 5.