Answer:
Step-by-step explanation:
Let X be the no of vehicles that require warranty service within I year out of vehicles sold (9) yesterday.
Each vehicle is independent of the other to get warranty service
Hence X is binomial with p=8% = 0.08
So P(X=x) = 

c) 
d) Mean = Mean of binomial = np =

Var (x) = npq = 
Std dev = square root of variance = 0.8139
Let’s write it simply, that helps us solve it easier.
6x^2+4x+8
Now, insert 7 in place of x.
6(7)^2+4(7)+8
Now, multiply.
42^2+28+8
Solve for exponents.
1,764+28+8
Add.
1,792+8
1,800
Hope this helps!
125 125x8=1000 1/8 of 1000 is 125
1.666666666666667 to be exact, but rounded it is 1.66