Can someone help me out?

5.(04.07) two different plants grow each year at different rates, which are represented by the functions f(x) = 4* and g(x) = 5x + 2. what is the first year the f(x) height is greater than the g(x) height? year 3 year 0 year 2 year 1

At the "no mutants allowed" country farm, every sheep has 4 legs, every chicken has two legs, and all animals have only 1 head. asked to count how many sheep and chicken are in the fields, a farm boy reports back that there are 140 feet and 50 heads. how many sheep and chicken are there? there are sheep and chicken at the farm.

1) prove that 731^3−631^3 is divisible by 100 2) prove that 99^3−74^3 is divisible by 25