Answer:
Equation system listed as (4)
Explanation:
There were only two deliveries - one on Monday and one on Tuesday. Each charged as a single fee f. On Monday, 2 dozens bagels were purchased, that is 2b, while on Tuesday 3 dozens were purchased, that is, 3b. And we know the invoices also: $8 (Mon), $11 (Tue), so
2b + f = 8
3b + f = 11
which is listed under choice (4).
If you are dying to know the cost of a dozen of bagels:
b = $3
and the delivery fee is $2