Need some help with these questions

Express the following as a function of a single angle, cos(60) cos(-20) - sin(60) sin(-20)

Which sentence describes why polygon mnop is congruent to polygon jklp? a. polygon jklp maps to polygon mnop through a translation. b. polygon jklp maps to polygon mnop through a rotation. c. polygon jklp maps to polygon mnop through a dilation. d. polygon jklp maps to polygon mnop through a stretch.

Asequence {an} is defined recursively, with a1 = 1, a2 = 2 and, for n > 2, an = an-1 an-2 . find the term a241