Answer:
The answer is B) 11.
Step-by-step explanation:
We can solve this by making an expression to represent the situation. Let x = the number of student books in the box (what we're looking for):






A graph of a proportional relationship is a straight line that passes through the origin. The constant of a proportionality in a graph of a proportional relationship is the constant ratio of y to x (the slope of the line).
The perimeter is 2,205 yards
9x0=0
9x1=9
9x2=18
9x3=27
9x4=36
9x5=45
9x6=54
9x7=63
9x8=72
9x9=81
9x10=90