A student wants to model the physical weathering of rock. Which activity could the student perform? A. Place several cookies in a box, and then shake the box.

B. Place ice cream in a bowl, and then watch it melt.

C. Place drops of acid on chalk, and then observe the chemical reaction.

D. Place a paper boat in a ditch, and then use water from a hose to make it sail away.

22. the top of a cliff is located a distance h above the ground. at a distance h/2 there is a branch that juts out from the side of the cliff, and on this branch a bird's nest is located. two children throw stones at the nest with the same initial speed, one stone straight downward from the top of the cliff and the other stone straight upward from the ground. in the absence of air resistance, which stone hits the nest in the least amount of time?