Inverse Trig

Find the measures for angles A and C. Round your answers to the nearest hundredth.

Let ∠D be an acute angle such that sinD=0.75. Use a calculator to approximate the measure of ∠D to the nearest tenth of a degree.

Let ∠D be an acute angle such that cosD=1/3. Use a calculator to approximate the measure of ∠D to the nearest tenth of a degree.

The Uniform Federal Accessibility Standards specify that a wheelchair ramp may not have an incline greater than 4.76°. You want to build a ramp with a vertical rise of 8 inches. You want to minimize the horizontal distance taken up by the ramp. Find the approximate dimensions of your ramp. Round decimal answers to the nearest tenth.

The horizontal part of a step is called the tread. The vertical part is called the riser. The recommended riser-to-tread ratio is 7 inches : 11 inches. Find the angle for stairs built using the recommended riser-to-tread ratio.  Round your answer to the nearest tenth.