The radius of a cylindrical popcorn tin is 3X +1 inches. the height of the tin is three times the radius what is the surface area of the cylinder?

Antonio made a scale model of a building. the model's scale is 1 inch to 235 feet and its height is 3.5 inches. what is the exact height of the actual building? enter your answer in the box.

How to do this , and can some one explain

Cot(90° − x) = 1 the value of x that satisfies this equation is °. a. 60 b. 135 c. 225 d. 315