2 x -6 equals 0. add 6 to both sides. divide both sides by two. x equals 3
Answer: a)
b) 
<u>Step-by-step explanation:</u>
a) In order to get an even number, you have the 3 different scenarios:
1) Even, Even, Even, Even 
2) Even, Even, Odd, Odd
3) Odd, Odd, Odd, Odd 
<em>Order doesn't matter</em>
Add them up to get your answer: 
b) If one die is a 2 and another is a 3 and the other two dice can be any number, then you have 1 possibility for a 2, 1 possibility for a 3, and 6 possibilities for each of the other two dice.

Answer:
b. =8.5+1.96*3/SQRT(45), and =8.5-1.96*3/SQRT(45)
Step-by-step explanation:
Sample size (n) = 45
Sample mean (M) = 8.5 minutes
Variance (V) = 9 minutes
Z-score for a 95% confidence interval (z) = 1.96
A confidence interval is defined by the following expression:

Applying the given data:

Writing in Excel statements, the limits of the interval would be
=8.5+1.96*3/SQRT(45), and =8.5-1.96*3/SQRT(45)
Therefore, the answer is alternative b.
A = {x ≥ 3}, B = {x ≤ 1}
So A∪B = {x ≥ 3 or x ≤ 1}
So for x ⊆(1,3), A∪B = ∅
Apparently, (1,3) covers the first option, a will be the answer