Answer:
b. It will decrease by a factor of 2
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence interval
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of
.
The lower end of the interval is given by:

The upper end of the interval is given by:

The length of the interval is the subtraction of the upper end by the lower end, so it is:

This means that the length is inverse proportional to the square root of the size of the sample.
So, if the sample size is multiplied by 4, the length of the interval is going to decrease by a factor of 2.
Answer:
The correct options are:
Option B)
is never zero.
Option F) When x=0, y≠0
Step-by-step explanation:
Consider the provided function.

When we substitute x=0 in above function we get:


When we substitute x=-1 in above function we get:


When we substitute x=1 in above function we get:


The above function is exponential function which does not pass through the origin and the range of the function is a positive number.
The graph of the function is shown in figure 1.
Now consider the provided options.
Option A)
is always greater than or equal to 1.
The option is incorrect as the value of the function is less than 1 for negative value of x.
Option B)
is never zero
The option is correct.
Option C) When y=0, x=0
The option is incorrect.
Option D) When x=0, y=4
When x=0 the value of y is 1.
Thus, the option is incorrect.
Option E)
is zero when x=0
When x=0 the value of
is 1.
Thus, the option is incorrect.
Option F) When x=0, y≠0
The option is correct as 0≠1.
We are not given tables, so will just use the amortization formula.

where
P=amount to be deposited today, to be found
A=amount withdrawn each year=18000
i=Annual interest=9%
n=number of years = 20
Substituting values,

=164313.82 to the nearest cent