Final answer:
The two-year plan is the least expensive if you want the subscription per year, with a cost of $22.97 per year.
Step-by-step explanation:
To determine which plan is least expensive per year, we need to calculate the cost per year for each plan. For the one-year plan, the cost is $24.97. For the two-year plan, the cost per year is $45.94/2 = $22.97. Finally, for the three-year plan, the cost per year is $74.91/3 = $24.97.
From the calculations, we can see that the two-year plan is the least expensive if you want the subscription per year, with a cost of $22.97 per year.