Given f(x) = x2 + 4, g(x) = x −5 what is (f º g)(x) = ?
and
given f(x) = x +1, g(x) = 2x, h(x) = x3
what is (h º g º f)(x)?
please give me a step by step explanation

Find a parametrization for the curve「and determine the work done on a particle moving along γ in r3 through the force field f: r^3--r^3'where f(x,y,z) = (1,-x,z) and (a) im (γ) is the line segment from (0,0,0) to (1,2,1) (b) im (γ) is the polygonal curve with successive vertices (1,0,0), (0,1,1), and (2,2,2) (c) im (γ) is the unit circle in the plane z = 1 with center (0,0,1) beginning and ending at (1,0,1), and starting towards (0,1,1)