Let f be a bounded function defined on the interval [a, b]. Mark each statement True or False. Justify each answer. (a) The upper and lower sums for f always form a bounded set. (b) If P and Q are...

Let f be a bounded function defined on the interval [a, b]. Mark each statement True or False. Justify each answer.

(a) The upper and lower sums for f always form a bounded set.

(b) If P and Q are partitions of [a, b], then P ∪ Q is a refinement of both P and Q.

(c) f is Riemann integrable iff its upper and lower sums are equal