i am stuck here solve this question

a) A real-valued function f(t) is called even if f(-t) = f(t) for all t and odd if f (-t) = -f(t) for all t. i) Sketch the graph of an even and an odd function. ii) Show that f(t)g(t) is even if both f (t) and g(t) are even, or if both f (t) and g(t) are odd. iii) Show that f(t)g(t) is odd if f (t) is even and g(t) is odd