1. D
2. D
I don't know the answer to number 3 sorry.
Answer:
that looks to be a 45 degree angle but I'm not sure
Answer:
The mean of the total repair time is 150 minutes.
The variance of the total repair time is 725 minutes^2.
Step-by-step explanation:
To solve this problem, we have to use the properties of the mean and the variance. Our random variable is the sum of 3 normal variables.
In the case, for the mean, we have that the mean of the sum of 3 normal variables is equal to the sum of the mean of the 3 variables:

For the variance, we apply the property for the sum of independent variables (the correlation between the variables is 0):

Answer:
-16
Step-by-step explanation:
When adding a negative and a positive number, you need to keep in mind that your are essentially adding.
so if I have a number line
-24, -23, -22, -21, -20, -19, -18, -17, -16, -15, -14,,,,
you will start at -24 and will go up the number line (to the right) 8 times and that should get you your answer.