Answer:
Since 60° is one sixth of the entire circle (360°) it means that the length of arc B is 1/6 th of the circumference.
1/6 * (12 * 2π) = 4π
what do you mean ¨ what is the distance between¨ what is the rest of the question?
In order to estimate the mean, you need to choose a value to represent the number in each category of accidents. It is often convenient to use the middle value of the range.
.. (4*6 +10*10 +15*6 +20*9)/(6 +10 +6 +9) = 394/31 ≈ 12.7