B is the answer
B- prices are all higher than 20$ all other of the answer choices are lower than 20$
We are asked to determine the area of the given figure. To do that we will divide the figure into a square and a triangle. The area of the square is the product of its dimension, therefore, the area is:

The area of the triangle is given by the following formula:

Where "b" is the base and "h" is its height. Replacing the values:

The total area is the sum of both areas:

replacing the areas:
Idk. "squirtle, use chortled attack!!!"
Answer:
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Step-by-step explanation:
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600 + 9.5x (less than or equal to) 900
600 fixed amount
9.5 is the variable changing amount and differs among number of students taken