I need help pls hurry

Abacteria population is tripling every hour. by what factor does the population change in 1/2 hour? select all that apply

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?

Common binomial factor of 6x(3x+7)+5(3x+7)