Calculating Consumer and Producer Surplus and Deadweight Loss

a)Calculate total consumer surplus at a price $8 and production of 6 million meals per day.

b)For the same equilibrium, calculate total producer surplus

If price remained at $8 but production were cut to 3 million meals per day:

c)Calculate Producer Surplus and Consumer Surplus

d)Calculate the deadweight loss from underproduction

My answer:

a)24CS  1/2bh
b)24PS  1/2bh
c)12CS  1/2bh 12PS 1/2bh
d)12DW

I'm rather lost in this subject of microeconomics.  An explanation would be helpful, so I could apply it to my other problem sets.  What am I missing?