Final answer:
Step-by-step explanation:
The inequality representing the amount Chris can purchase with $120 is 9L+6S≤120 (option a).
This inequality represents the total cost of purchasing lobsters (L) and shrimp (S). The coefficient of L is 9 and the coefficient of S is 6, which indicates the cost per pound of each item. The left side of the inequality represents the total cost of the purchase and it must be less than or equal to $120.
For example, if Chris wants to buy 10 pounds of lobster and 5 pounds of shrimp, the total cost would be 10(9) + 5(6) = 90 + 30 = $120, which satisfies the inequality.