Answer:
To calculate the diameter of a circle, multiply the radius by 2. If you don't have the radius, divide the circumference of the circle by π to get the diameter. If you don't have the radius or the circumference, divide the area of the circle by π and then find that number's square root to get the radius.
Step-by-step explanation:
3u + 4u + 2u = 9u
9u = 90
1u = 90/9 = 10
since black is 2u ( from the ratio given)
2u = 10 x 2 = 20
Answer : 20cm of the pole is painted black.
The bar diagram is in the picture :)
Answer:
cot(x)
Step-by-step explanation:



Recall the Pythagorean Identity 
It would be $18.94, because the hundredths place is the penny.