What is the least common factor for 1,000 and 150

Hi my sisters and brothers can tell me the answer because i don’t understand the question

The marriott family bought a new apartment three years ago for $65,000. the apartment is now worth $86,515. assuming a steady rate of growth, what was the yearly rate of appreciation? what is the percent of the yearly rate of appreciation?

If f(x) = 2x + 8 and g(x) = x4, what is (gº)?