Final answer:
The function rule for the cost of the t-shirts is C(n) = 35n + 1.75, where n represents the number of t-shirts bought, $35 is the price per t-shirt, and $1.75 is the one-time handling fee.
Step-by-step explanation:
The function rule that models the cost of the t-shirts includes both the price per t-shirt and the one-time handling fee. If we denote the number of t-shirts bought as n, then the total cost C(n) can be represented by the equation C(n) = 35n + 1.75, where $35 is the cost per t-shirt and $1.75 is the handling fee, which does not depend on the number of t-shirts purchased.
For example, if someone were to buy 10 t-shirts, the total cost would be C(10) = 35(10) + 1.75 = 350 + 1.75 = $351.75.