Approximating Areas With Riemann Sums Practice Test

Let $$g$$ be a function that is strictly decreasing on the interval $$a, b$$. Which of the following statements provides the best comparison between the right Riemann sum approximation ($$R_n$$) and the true value of the integral $$\int_a^b g(x) dx$$?

Let $$f$$ be a function such that $$f'(x) < 0$$ and $$f''(x) < 0$$ for all $$x$$ in the interval $$a, b$$. Let $$I = \int_a^b f(x) dx$$. For a given number of subintervals $$n$$, which of the following must be true about the left Riemann sum ($$L_n$$) and trapezoidal sum ($$T_n$$) approximations?