The right option is; b. the water caused an increase in temperature of the air inside the ball and an increase in pressure.
The dent (hollow area formed by pressing or hitting) from the ping-pong ball disappeared because energy was transferred from the hot boiling water in which the ball was placed to the air inside the ball. This transferred energy will increase the temperature of the air inside the ball and the air molecules will begin to move faster with a greater force. Hence, causing an increase in pressure.
Answer:
If i am not mistaken, that would the the cell membrane, made out of lipids and different proteins.
A.
Commuters drive personal vehicles to their places of work: offices, manufacturing plants etc.
Some may use car pooling or mass transit like buses. But too many want the luxury and convenience of coming and going on their own terms.
IMHO car pooling and mass transit needs to be used more to reduce environmental harm.