Answer:
(1)
(2)


Explanation:
For this case we can put some notation
Let b= dozen bagels and f= delivery fee
And for this case we know that "On Monday, they delivered two dozen bagels, b, to an office at a total cost of $8", so then the total taling in count the delivery fee we have this:

And for the other part "On Tuesday, three dozen bagels were delivered at a total cost of $11", we can write the expression like this:

And our system of equations would be:
(1)
(2)
If we solve for f from equation (1) we got:

And if w replace this into equation (2) we got:

And solving for f we got:
