You need to include the actual picture of the graph :)
I hope it helps you get it right right
Answer

Step-By-Step Explanation
Given the function
.
For each pair (t, f(t)) in the data points (0,5.5), (π/2,0.5), (π,−2.5), (3π/2,−7.5)
.
.
.
.
Expressing this as a system of linear equations in matrix form AX=B
Where
,

To determine the values of X, we use the expression

Therefore:
Therefore, the trigonometric function which fits to the given data is:

Answer:
median is 90
Step-by-step explanation:
75, 88, 92, 100
(88+92)/2 = <u>90</u>