Hello there.
We have for a circle that:

Where:
is the measure of the arc
is the measure of the angle (radians)
is the radius of the circle
In our case, we have 
We have r = 3 cm, then:

Step-by-step explanation:
personal- 347 ÷ 809 = 0.43%
lap top- 398 ÷ 809 = 0.49%
printer- 64 ÷ 809 = 0.08%
I don't know what your asking