Answer:
Question 13: For age groups y=1 and y=1.3 response is 8 microseconds.
Question 14: The club was making a loss between 11.28 and 4.88 years.
Step-by-step explanation:
Question 13:
The age group y for which the response rate R is 8 microseconds is given by the solution of the equation

We graph this equation and find the solutions to be

Since only positive solutions for y are valid in the real world we take only those.
Thus only for age groups y=1 and y=1.3 the response is 8 microseconds.
Question 14:
The footbal club is making a loss when 
Or

We graph this inequality and find the solutions to be
and 
Since in the real world only positive values for t are valid, we take the the second solution to be true.
Thus the club was making a loss in years 
Answer:
18s+20b<_150
Step-by-step explanation:
He can buy 5 basketballs and 2 soccer balls. This equation is correct because 18x2 is 36 and 20x5 is 100. So that will be a total of $100. This makes the equation 100<_150. You can infer that this equation is true.