It is A. Barium
Explanation: I did that already
Answer:
the pig's average speed is 7 m/s
because it can influence how frequently and sufficiently the particles collide depending on the space it has to do so, for example a large surface area would be have a slower rate of reaction and a lower temperature. (the rate of reaction in terms of concentration, it is diffused from high to low)
The answer is b. The ball of paper, because it is more affected by gravity