Drake buys a ring that costs $8,000, which depreciates at a rate of 9.5% per year. What is the value of Drake's ring after 7 years? Round to the nearest cent.

You are standing next to a really big circular lake. you want to measure the diameter of the lake, but you don't want to have to swim across with a measuring tape! you decide to walk around the perimeter of the lake and measure its circumference, and find that it's 400\pi\text{ m}400? m. what is the diameter dd of the lake?

Tom drove 206 miles in 3.9 hours. estimate his average speed.

Peter measures the angles in a triangle. he finds that the angles are 95, 10 and 75. is he correct? explain your answer