each item costs $8.
Total number of items = n
total cost = 8n

cost for postage:
1st item = $3
remaing at $1 each
remaining items = n-1
total postage = 3 + n - 1 = n +2

total cost = 8n + (n + 2) = 9n + 2

Alternatively, you could plug in numbers….

Let n = 2 (any number will work)

$8 * n = 8 * 2 = 16 (price before postage and handling)
3$ (postage/handling for the first item)
1$ (postage/handling for the second item)

16 + 3 + 1 = 20 (Total price including shipping)

Now, plug in the “2” in each answer….

C) 9n + 2 = (9*2) + 2 = 20