The circumference of a circle is 78π cm. Find the diameter, the radius, and the length of an arc of 140°.

A. 156 cm; 39 cm; 160π cm

B. 39 cm; 78 cm; 15.2π cm

C. 78 cm; 156 cm; 15.2π cm

D. 78 cm; 39 cm; 30.3π cm

The correct answer is the option D, which is: D. 78 cm; 39 cm; 30.3π cm

The explanation is shown above:

1-The formula for calculate the circumference of a circle is:

C=2 πr

78π=2πr

2 - The radius is:

r=78π/2π

r=39 cm

3 - The diameter is:

D=39 cm x 2

D=78 cm

4 - The arc length is:

arc length = (140°π/180°) (39 cm)

arc length=30.3π cm