Mosquitoes are annoying insects. To eliminate mosquito larvae, a certain granular substance can be applied to standing water in a ratio of 1 tsp per 30 sq ft of standing water. a. At this rate, find how many teaspoons of granules must be used for 720 sq ft.
b. If 3 tsp = 1 tbsp, how many tablespoons of granules must be used?

a. __ teaspoons of granules must be used.
b. __ tablespoons of granules must be used.