65. Odds and Evens There are four odd functions and three even functions in the gallery of twelve basic functions. After multiplying these functions together pairwise in different combinations and exploring the graphs of the products, make a conjecture about the symmetry of:
(a) a product of two odd functions;
(b) a product of two even functions;
(c) a product of an odd function and an even function.

[-4.7, 4.7] by [-3.1, 3.1]
(a)

[-4.7, 4.7] by [-3.1, 3.1]
(b)