Answer:
part a is A and E
Step-by-step explanation:
I had token the test
Answer:
44 units
Step-by-step explanation:
Since B is the mid-point of AC
AB=BC
or,4x+14=x+20
or, 4x-x=20-14
or 3x=6
or,x=6/3=2
AC=AB+BC
= 4x+14+x+20
= 4(2) + 14 +2 +20
= 8+14+22
=44 units
Let
be the time it takes for pumps A, B, and C (respectively) to fill 1 tank. Then

Now,

Then

This means

and

Working together, all 3 pumps would operate at a rate of

or 1 tank in 1 hour, so the answer is D.
Answer:
99.89% of students scored below 95 points.
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:

What percent of students scored below 95 points?
This is the pvalue of Z when X = 95. So



has a pvalue of 0.9989.
99.89% of students scored below 95 points.