Need help asap please

What basic trigonometric identity would you use to verify that sin x cos x tan x =1-cos^(2)x?

David must install fencing around a lot that is shaped like a right angle. the side of lot that runs east-west is 200 ft long. the side of the lot runs north-south is 125 ft long. calculate how many feet of fencing he will need to surround the entire lot.

Let f(x) = x+3 and g(x) = 1/x the graph of (fog)(x) is shown below what is the range of (fog)(x)?