What happens when layers of snow keep piling up?

fast i have to have it by 1: 00 west !

a. the bottom layers are compressed into ice
b. the top layers melt into water.
c. the top layers are compressed into ice
d. the bottom layers melt into water

For the reaction shown, calculate how many moles of no2 form when each of the following completely reacts. 2n2o5(g)→4no2(g)+o2(g) part a 1.0 mol n2o5 express your answer using two significant figures. nothing mol m o l request answer part b 5.4 mol n2o5 express your answer using two significant figures.