First one
The period is 2pi - (-6pi) = 8pi
Second one
A) The max ht = 55 and the min ht = 5
So...the radius = (55 - 5) / 2 = 50 / 2 = 25 m .....so ...TRUE!!
B) False....the car is loded at its min ht of 5....at 0 sec the ht = 30 m
C ) False....the max ht = 55m
D) TRUE !!!