If the density of a full can is 1.1g/cc what is it’s mass? the height of the can is 12cm the area of top is 40cm squared

I'm terrible at math any here is appreciated.

Extra points! find the missing dimension! need asap

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?