Answer:
6 buckets
Step-by-step explanation:
Look at the ratio:
1/3 cup kernels : 2 quarts popcorn
2/3 cup kernels : 4 quarts popcorn : 1 bucket . . . . multiply by 2
2 cups kernels : 3 buckets . . . . . . . . . . . . . . . . . . . . .multiply by 3
4 cups kernels : 6 buckets popcorn . . . . . . . . . . . . multiply by 2