The equation y=1.25x represents the cost (y) to buy (x) granola bars at the snack shop. The table shows the cost of granola bars at the sports field. Which location sells granola bars for a lower price

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?