9. What is the surface area of a tennis ball with a diameter of 2.6 Inches? Use 3.14 for pl and round to the nearest hundredth. O 5.31 sq in
10.61 sq in
O 8.16 sq in
O 21.23 sq in

D: 21.23 sq in

Step-by-step explanation:

A tennis ball is a sphere, so we're going to use the surface area of a sphere formula. (4πr²)

Remember that radius is HALF of the diameter, which in this case is 2.6. This means the radius is 1.3.

π represents 3.14

Once you plug the values into the above equation, you should receive the above answer.

x + y = 90 5x – 10y = 90 90 – 10y = 5x 90 + 10y = 5x

step-by-step explanation:

last month maria hiked the 5-mile mountain trail a number of times and she hiked the 10-mile canal trail several times. let x represent the number of times she hiked the 5-mile trail, and let y represent the number of times she hiked the 10-mile trail. if she hiked a total of 90 miles, which equation can be used to find the number of times maria hiked each trail? x + y = 90 5x – 10y = 90 90 – 10y = 5x 90 + 10y = 5x