The vertices of a triangle have the coordinates A(3,4), B(-2,-1), and C(-7,6). Determine if it is a right triangle? Justify your response.(somebody please answer quick)

I'm terrible at math any here is appreciated.

Which of the following is most likely the next step in the series? a3z, b6y, c9x, d12w, е15v, f18u

Scarlet bought three pairs of sunglasses and two shirts for $81 and paula bought one pair of sunglasses and five shirts for $105 what is the cost of one pair of sunglasses and one shirt?