Can somebody answer this?

Which math sentence can be used to determine if the triangle is a right triangle?

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.

Complex numbers multiply √-4 * √-25 and show all intermediate steps. alternative notation is sqrt(-4) * sqrt(-25).