A. Like charges repel each other. Just think opposites attract for charged particles.
Answer: 99% confidence interval would be (45.74,54.26).
Step-by-step explanation:
Since we have given that
N = 18
Mean = $50
Standard deviation = $7
At 99% confidence level, z = 2.58
So, Interval would be

Hence, 99% confidence interval would be (45.74,54.26).
Use Pythagorean's Theorem to find the length of x.

so

and

. We can simplify that radicand down into a perfect square times a prime number, and that is

. 4 is a perfect square that can be pulled out as a 2, so the length of x is

, the choice on the top right.
Answer:
6.4 rounds down to 6.
Step-by-step explanation:
Divide 16 by 5. Multiply that number by 2.