If 5% of an amount equals 800,000, then what is that amount? Please I confused, can someone help me!

Find the smallest number by which the given number should be divided to make a perfect cube(with steps or the answer will get reported) a.108 b.2187

If f(x)=-x^2+6x-1 and g(x)=3x^2-4x-1,find(f+g)(x)

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?