Answer:
Speed of the soccer ball with respect to ground is ZERO
Explanation:
As we know that truck is moving with speed 20 mph
Now a soccer ball is shoot from truck with respect to the motion of truck in opposite direction
The relative speed of the soccer ball is

now we know that

so we have

so we have

B sleeping because your body is allowed to relax and when you fall asleep everything slows down including your heart rate (that is why sometimes you will just randomly wake up in the middle of the night because your heart rate is very low)
Im saying a or b but i pick B
A) When the angle between the Force (F) and Displacement (x) is 0°, because, Work done (W) is directly proportional to the Cosine of the Angle between the Force applied and the resultant displacement of the subject.
W = F•x cos ∅
If ∅ = 0°,
W = F•x ===> Maximum Work Done.
If ∅ = 45°,
W = F•x/√2
If ∅ = 90°,
W = 0
If ∅ = 180°,
W = –F•x ===> Minimum Work Done.
Answer:
factor that changes because of the manipulated variable: A. Manipulated variable
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