Answer:
the answer is (a) 28.
Explanation:
The given situation can be represented by a linear equation of the form:
Cost = mx + b
where "m" is the slope (the rate of change of cost with respect to time), "x" is the number of hours of the tour, and "b" is the y-intercept (the cost when x = 0).
In this case, the y-intercept is $60, which represents the one-time fee. The cost increases by $28 per hour, so the slope is:
m = $28/hour
Therefore, the answer is (a) 28.