I think the answer is wind
Answer:
B. It begins to rotate counterclockwise
Explanation:
It can happen that the merry-go-round remains at rest in the case when the person is standing on the axle of the merry go round whose axis is fixed to some rigid support, but here the person is standing at the center of the merry-go-round not at the axle hence the according to the conservation of angular momentum. Angular momentum is given as:

for the conservation of momentum

where:
moment of inertia of the merry-go-round
angular velocity of the merry-go-round
moment of inertia of the bicycle wheel
angular velocity of the wheel
As the person tries to stop the wheel which is rotating then the person feels an opposing force which tries to moves the whole system in its direction.
<u>Answer:</u>
1) Distance traveled by bird = 403 meter
2)Average speed = 1.66 km /hour
3) Zcceleration = 2 
<u>Explanation:</u>
1) Distance traveled = Speed * Time taken = 31 * 13 = 403 meter.
2) Average speed = Total distance covered / Time taken for that distance to cover.
Total distance covered = 2+0.5+2.5 = 5 km
Time taken = 3 hours
Average speed = 5/3 = 1.66 km /hour
3) Acceleration is defined as the rate of change of velocity, so acceleration a = change in velocity/time.
Change in velocity = 14 - 6 = 8 m/s
Time = 4 seconds
So acceleration = 8 / 4 = 2 
After doing some research on Wiki, Google, and Easyscienceforkids, I have come to a conclusion that:
Mass: 5.972 * 10^24 kg
Radius: 3958.8 mi
Distance from the sun: 92.96 million mi
Explanation:
It is given that,
Radius of the circular orbit,
Speed of the electron, 
Mass of the electron, 
(a) The force acting on the electron is centripetal force. Its formula is given by :


(b) The centripetal acceleration of the electron is given by :



Hence, this is the required solution.