Which statements describe physical weathering? select all that apply. a. two rocks hit against each other in a fast-flowing stream and break apart. b. oxygen and water change the compostion of the minerals in a rock c. small rocks are pushed together when a mole digs an underground den d. mosses grow on a rock and produce acids that wear away the rock over time.

Calculate the ratio of h+ ions to oh– ions at a ph = 6. find the concentration of h+ ions to oh– ions listed in table b of your student guide. then divide the h+ concentration by the oh– concentration. record this calculated ratio in table a of your student guide. compare your approximated and calculated ratios of h+ ions to oh– ions at a ph = 6. are they the same? why or why not? record your explanation in table a. what is the concentration of h+ ions at a ph = 6? mol/l what is the concentration of oh– ions at a ph = 6? mol/l what is the ratio of h+ ions to oh– ions at a ph = 6? : 1

A100 kg running back runs at 5m/s into a stationary linebacker. it takes 0.5 for the running back to be completely stopped

What does the law of conservation of mass state?