Finding missing angles

The graph below shows the price of different numbers of mats at a store: a graph is shown. the values on the x axis are 0, 2, 4, 6, 8, 10. the values on the y axis are 0, 21, 42, 63, 84, and 105. points are shown on ordered pairs 0, 0 and 2, 21 and 4, 42 and 6, 63 and 8, 84. these points are connected by a line. the label on the x axis is number of mats. the title on the y axis is price in dollars. which equation can be used to determine p, the cost of b mats?

The size of a certain cell is 2.5*10^-9m. another cell is 1.5*10^3 times larger. how large is the larger cell in scientific notation?

I’m on question 7 it says a covered water tank is in the shape of a cylinder the tank has a 28 inch diameter and a height of 66 inches to the nearest square inch what is the surface area of the water tank