Answer:
Part 1) 
Part 2)
Part 3) 
Part 4) 
Step-by-step explanation:
Part 1) Find the measure of arc AB
we know that
----> by central angle
we have

therefore

Part 2) Find the measure of arc ABC
we know that
The central angle of complete circle is equal to 360 degrees
so
Part 3) Find the measure of arc BAC
we know that
----> by angle addition postulate
we have
---> by central angle
---> by central angle
so

Part 4) Find the measure of arc ACB
we know that
The central angle of complete circle is equal to 360 degrees
so

substitute

Answer:
To obtain a valid approximation for probabilities about the average daily downtime, either the underlying distribution(of the downtime per day for a computing facility) must be normal, or the sample size must be of 30 or more.
Step-by-step explanation:
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean
and standard deviation
, the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean
and standard deviation
.
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean
and standard deviation 
In this question:
To obtain a valid approximation for probabilities about the average daily downtime, either the underlying distribution(of the downtime per day for a computing facility) must be normal, or the sample size must be of 30 or more.
7/9 = 14/18
14-5=9
9/18=1/2
1,386
is the answer hope this helped