I think B is the most correct, because logically it's harder to bend a stiffer spring than it is to bend a softer one. Also, I don't think length comes into play. So B.
Answer:
The voltage of the battery
Answer:Paper and plastic!
Explanation:
-- The net force on the box is 2N to the left.
-- The box will move to the left and accelerate to the left.
-- F=ma . a=F/m . a=(2N)/(4kg).
a = 0.5 m/s^2 to the left.
Sounds are created when something vibrates (shakes back and forth), sending waves of vibrations into the ears of the listener. When a bell is struck, the metal vibrates. The vibrations travel through the air as sound waves.
hope this helps