How do I answer this pls tell me ​

What is the answer to the question 5x+2x

If f(x) = 4x - 3 and g(x) = x + 4, find (f - g) (x)

Astocks price gained 3% in april and 5% in may and then lost 4% in june and 1% in july during which month did the stocks price change the most