Linda bought a total of 12 lb of flounder and shrimp and paid $20 for the flounder and $20 for the shrimp. If the price per pound of the shrimp is twice that of the flounder, how many pounds of each did she buy? Select one:

a.
8 lb shrimp and 4 lb flounder

b.
4 lb shrimp and 8 lb flounder

c.
6 lb shrimp and 6 lb flounder

d.
2 lb shrimp and 10 lb flounder