12. A ball of mass m is attached to the end of a string of length Q as shown above. The ball is released from rest from position P . where the string is horizontal. It swings through position Q . where the string is vertical, and then to position R . where the string is again horizontal. What are the directions of the acceleration vectors of the ball at positions Q and R ?
Position Q
(A) Downward
(B) Downward
(C) Upward
(D) Upward
## Position R
Downward
To the right
Downward
To the left