**Answer:**

The inequality representing s, the number of sets of forks Nathan should buy is

s ≥ 21

**Step-by-step explanation:**

From the question, the restaurant needs at least 571 forks, i.e., if n represents the number of forks the restaurant needs, then

n ≥ 571

Also from the question, there are currently 361 forks. If y represents the number of forks the restaurant needs to buy, then

y ≥ 571 - 361

y ≥ 210

Also, each set on sale contains 10 forks. if s represents the number of sets of forks Nathan should buy, then

s ≥ 210/10

s ≥ 21

Hence, the inequality representing s, the number of sets of forks Nathan should buy is

s ≥ 21