I think it is b , that what I would i pick
Explanation:
It is given that,
Length of the helicopter, l = 3.1 m
The helicopter rotates, the length of helicopter will become the radius of circular path, r = 3.1 m
Angular speed of the helicopter, 
(a) The centripetal acceleration in terms of angular velocity is given by :



(b) Let v is the linear speed of the tip. The relation between the linear and angular speed is given by :


v = 90.89 m/s

Hence, this is the required solution.
The finer‐grained<span> s</span>edimentary rocks<span> are called shale, siltstone, and mudstone</span>
Here, E<span>ach kilogram of mass weighs 9.8 newtons as it's unit value of it.
In short, Your Answer would be Option D
Hope this helps!</span>