Constraints !

mr. weber drives to a landscape supply center to buy sand and gravel. the center has 6 lb of sand and 13 lb of gravel in stock. mr. weber needs at least 2 lb of sand. the amount of gravel he will buy will be at least twice the amount of sand he will buy.

mr. weber buys 7 lb of gravel. how much sand can he buy?

choose all answers that are correct.

a 2 lb
b 3 lb
c 4 lb
d 5 lb
e 6 lb