If the slope if the line a is -4 and line a is perpendicular to line b. Which statement must be true?

Issof claims that the scale factor is 1/2. which statement about his claim is correct

Acomputer store bought a program at a cost of $10 and sold it for $13. find the percent markup

List x1, x2, x3, x4 where xi is the left endpoint of the four equal intervals used to estimate the area under the curve of f(x) between x = 4 and x = 6. a 4, 4.5, 5, 5.5 b 4.5, 5, 5.5, 6 c 4.25, 4.75, 5.25, 5.75 d 4, 4.2, 5.4, 6