15 I helped someone with this question already so I know its right
Answer:
B
Step-by-step explanation:
For answer A it is stretching the graph of function f by a factor of 15.
For answer C and D it is changing the function itself and that is not what the question is asking.
The coefficient 6 represents the price for an hour of bike rental.
First we need to count the total number scores. This can be done from the stem and leaf plot. The total number of scores are 19. The total number of values is odd, so the median position will be:

Thus the 10th score is the median score for the class of Mr. Robert. The 10th score from the stem and leaf plot is 81.
Thus 81 is the median score of Mr. Robert's Class.
The shape that is generated is a Cone.
A triangle, when rotated about one of it's side will generate a solid in a form of a Cone. The cone could be a hollow one or a solid filled one, depending on the properties of the triangle being rotated.