Answer:
By the Empirical Rule, 
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviation of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
The symbol of a standard deviation is
. So
When plotting sample statistics on a control chart, 99.7% of the sample statistic values are expected to fall within plus/minus how many sigma?
By the Empirical Rule, 
Answer:
45
Step-by-step explanation:
1/3 of 90
= 1/3 * 90
= 90/3
= 30
Let the missing number be x.
2/3 of x
= 2/3 * x
= 2x/3
30 = 2x/3
Cross multiply,
2x = 30 * 3
2x = 90
x = 90/2
x = 45
Hence,
the missing number is 45.
To find X and Y X is horizontal Y is vertical, so that means SCP is horizontal and EF or a B is oops sorry all the way around
C. For sure. Hope it helps