B. The number of field lines on the source charge.
Answer: i guess d is the correct answer
Answer:
7 s
Explanation:
u = Initial velocity of rock = 12.2 m/s
= Angle of throw = 
x = Displacement in x direction = 25 m
Displacement in x direction is given by

Time taken to reach the ground is 7 s.
H. O is the answer hope this helps
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