Using the z-distribution, it is found that the lower bound of the 99% confidence interval is given by:
d. 68.39%.
<h3>What is a confidence interval of proportions?</h3>
A confidence interval of proportions is given by:

In which:
is the sample proportion.
In this problem, we have a 99% confidence level, hence
, z is the value of Z that has a p-value of
, so the critical value is z = 2.575.
The sample size and estimate are given by:

Hence, the lower bound is given by:

Hence the lower bound is of 68.39%, which means that option D is correct.
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Answer:
Option 1 and Option 4
Step-by-step explanation:
The rest are just wrong.
Answer:
The electric field generated by a point charge is given by:
where
is the Coulomb's constant
Q is the charge
r is the distance from the charge
We want to know the net electric field at the midpoint between the two charges, so at a distance of r=5.0 cm=0.05 m from each of them.
Let's calculate first the electric field generated by the positive charge at that point:
where the positive sign means its direction is away from the charge.
while the electric field generated by the negative charge is:
where the negative sign means its direction is toward the charge.
If we assume that the positive charge is on the left and the negative charge is on the right, we see that E1 is directed to the right, and E2 is directed to the right as well. This means that the net electric field at the midpoint between the two charges is just the sum of the two fields:
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Step-by-step explanation:
B.
You would first have to add 9 to each side so that the equation equaled 0. Then you could pull these numbers.