Answer:
a) 
And replacing we got:
b) 
And then the expected value would be:
Step-by-step explanation:
We assume the following distribution given:
Y 0 1 2 3
P(Y) 0.60 0.25 0.10 0.05
Part a
We can find the expected value with this formula:
And replacing we got:
Part b
If we want to find the expected value of 
we need to find the expected value of Y^2 and we have:
And replacing we got:
And then the expected value would be:
306/6 is 51 is you add one to one side and take away the other the six numbers become: 46, 48, 50, 52, 54, 56 as you added one to one side substituting the other you took away from, therefore the smallest would be 46.
I not that good with math but I would say C.
Answer: C) 42.3 cm^2
formula for the area if a trapzoid:
A= .5*(b1+b2)*h
A= .5(5.6+8.5)*6
A= 42.3
Each of the 4 friends spent 15 dollars so all you need to do is multiply 4 by 15. 4x15=60
