Answer:

Step-by-step explanation:
Notice when x increases 1, y is 4 times the previous one, so
the function is like 
To determine the constant C, put any pair of (x, y)
Use x = 0, y = 0.2, so
0.2 =
= C * 1 = C
then 
Answer:
2019.
Step-by-step explanation:
We have been given that for the years from 2002 and projected to 2024, the national health care expenditures H, in billions of dollars, can be modeled by
where t is the number of years past 2000.
To find the year in which national health care expenditures expected to reach $4.0 trillion (that is, $4,000 billion), we will substitute
in our given formula and solve for t as:




Take natural log of both sides:





So in the 18.5 years after 2000 the expenditure will reach 4 trillion.

Therefore, in year 2019 national health care expenditures are expected to reach $4.0 trillion.
Answer:
The 80% confidence interval for the mean number of toys purchased each year is between 7.5 and 7.7 toys.
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of
.
That is z with a pvalue of
, so Z = 1.28.
Now, find the margin of error M as such

In which
is the standard deviation of the population and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 7.6 - 0.1 = 7.5
The upper end of the interval is the sample mean added to M. So it is 7.6 + 0.1 = 7.7
The 80% confidence interval for the mean number of toys purchased each year is between 7.5 and 7.7 toys.
Answer:
7)141
8)65
Step-by-step explanation: