300% increase of 25 (pls include steps)

Identify the number as a rational or irrational.explain. 127

Will mark name all segments skew to bc

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?