Answer: I think it's b.
Step-by-step explanation:
for number 1 its mixed numbers...and number 2 is The denominator
We can rewrite the asked question like this:

wherein X_1 and X_2 are random variable with the same given normal distribution. Then mean of

is zero and the variance
can be computed like this:

So, the random variable

follows a normal distribution
with means 0 and standard deviation 9.6.
The median of the law N(0,9.6) is 0.
So the expected difference of the score is 0.
Answer:
(x - 6)(x + 4)(x - 2)
Step-by-step explanation:
since x = 6 is a root then (x - 6) is a factor
x³ - 4x² - 20x + 48 ÷ (x - 6)
= (x - 6)(x² + 2x - 8)
= (x - 6)(x + 4)(x - 2) ← factors of f(x)