“The breaking distance is directly proportional to the square of its speed”
Using your variables, this means: d = k•b^2
k here is some unknown (and for this question irrelevant) number.
Now if b (the speed) is increased by 200%, then your new speed is b+2b = 3b. The 2b is the 200% increase.
Throw 3b into the first equation we have the new d as:
d = k • (3b)^2
Simplifying this, you have d = k•9b or d=9kb
This means the new braking distance is 9 times the original braking distance.
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:

Answer:
cos B = 8/17
Step-by-step explanation:
The cosine function is defined as (adjacent side) / (hypotenuse), and in this case is 8/17.
-2(-2)+3=7
-2(0)+3=3
-2(4)+3=-5