Is this arithmetic or geometric? 1, 4, 16, 64

The function a represents the cost of manufacturing product a, in hundreds of dollars, and the function b represents the cost of manufacturing product b, in hundreds of dollars. a(t) = 5t + 2 b(t) = 7t - 2t +4 find the expression that describes the total cost of manufacturing both products, a(t) + b(t). a. 7t^2 - 7t + 2 b. 7t^2 + 3 +6 c. 7t^2 + 7t - 6 d. 7t^2 - 3t + 6

Aye asap pls ! markin da brainiest too ! btw da step choices are all add, distribute, divide, n subtract

Find the vertex for the parabola given by the function ƒ(x) = −3x2 − 6x.