Determine whether each of the statements that follow is true or false. If a statement is true, explain why. If a statement is false, provide a counterexample.
(a) True or False: $\int g^{\prime}(h(x)) h^{\prime}(x) d x=g(h(x))+C$.
(b) True or False: If $v=u^{2}+1$, then $\int \sqrt{u^{2}+1} d u=$ $\int \sqrt{v} d v$
(c) True or False: If $u=x^{3}$, then $\int x \sin \left(x^{3}\right) d x=$ $\frac{1}{3 x} \int \sin u d u$
(f) True or False: $\int_{2}^{4} x e^{x^{2}-1} d x=\frac{1}{2} \int_{2}^{4} e^{u} d u$.
(g) True or False: $\int_{2}^{3} f(u(x)) u^{\prime}(x) d x=\int_{u(2)}^{u(3)} f(u) d u$.
(h) True or False: $\int_{0}^{6} f(u(x)) u^{\prime}(x) d x=\left[\int f(u) d u\right]_{0}^{6}$.
(d) True or False: $\int_{0}^{3} u^{2} d u=\int_{x=0}^{x=3}(u(x))^{2} d u$.
(e) True or False: $\int_{0}^{1} x^{2} d x=\int_{0}^{1} u^{2} d u$.