Need to know in 30 minutes! i don't know it. i need answers.

There are 15 plates and each plate is either 7 or 12 inches diameter. which systems of equations do you use to find the number of 7 inch plates, x and 12 inch plates, y

Complete the steps, which describe how to find the area of the shaded portion of the circle. find the area of the sector by multiplying the area of the circle by the ratio of the to 360. subtract the area of the triangle from the area of the sector.

{0,1,2,3,4,5,6,20,21,22,23,24,25} the distribution is considered to be: skewed the right, skewed the left, not skewed?