12. Need help

12. Suppose f(x) is a continuous and differentiable function. State whether each of the following is always true, sometimes true, or never true. Justify your answers with a theorem, graph, or 8 pts explanation. a . - Saf ( x ) dx = SE f (x ) dx b. Saf (x ) dx = 0 c. Sof ( x ) dx = Elf ( x ) Ax d. S* f (x) dx represents the net area under the curve F(x)