Can you help me with this question please

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

An equation of the line tangent to y=x^3+3x^2+2 at its point of inflection is

I'm confused on this could anyone me and show me what i need to do to solve it.