Circles: Area and Circumference, Auto-Gen

Which of the following is the formula for the CIRCUMFERENCE of a circle? (Select all that apply)

•  $2\pi r$  

•  $\pi d$  

•  $2\pi r^2$  

•  $\pi r^2$  

• 8322.13

• 1134.11

• 4536.46

• 1267.09

Find the exact area of the semicircle.

• 32 π cm²

• 64 π cm²

• 16 π cm²

• 8 π cm²

What is the area of this circle?

Use 3.14 for pi

• 82.13 m²

• 78.50 m²

• 314.16 m²

• 170.12 m²

Find the area of the figure.

Use 3.14 for pi

Is the red line a radius or diameter of the circle?

• Radius

• Diameter

Find the perimeter of the semicircle.

Use 3.14 for pi

• 12.86cm

• 20.56cm

• 25.12cm

• 50.24cm

Alex has trained his puppy, Popper, to jump through a ring. According to Alex's measurements and calculations, the ring has a diameter of 3.5 feet. What is the ring's circumference (use 3.14 for pi)?

• 11.32 ft
• 12.25 ft
• 10.99 ft
• 8.75 ft

The area of this circle is 78.5 units².

What is the radius? (use 3.14 for pi)

• 25

• 5

• 50

• 12.5

What is the diameter of this circle?

• 3.5
• 6.5
• 6
• 7