1) The questions are:
i) What is the maximum profit the florist will earn?
ii) What is the break-even
iii) What is the interval in chich the florist makes profin?
Answers:
1) The graph is a parabola in which the function p(x) is the profit and x is the number of one-dollar decreases
The vertex of the parabola is the maximum of the function, so that tells the number of one-dollar decreases for which the maximum profit is earned.
The vertex shown in the graph is (5, 675).
If you have problems reading the number 5, you can calculate it because it is the middel point between the two x-intercepts, i.e (20 - 10) / 2 = 10 / 2 = 5.
Therefore, the maximum profit earned is $675 and it is when the number of one dollar decreases is 5. ← first answer
2) Break-even means that the florist will not either earn or lose, which is the same that the profit is zero.
In the graph, the profit zero is the x-intercept. That is x = 20 (the negative portion of the graph is not part of the domain because the variable x has to be positive).
So, the answer is 20 one dollar decreases. ← second answer
3) The interval of the number of one-dollar dicreases for which the florist make a profit is the interval (0,20), as x is a whole number that is equivalent to [1,19] ← third answer
