Answer:
Step-by-step explanation:
9000-500h=0+500h
h= 9 hours
Here's the solution,
The given triangle is an <u>equilateral triangle</u>, because it's all angles measure 60° each
now,
Area of an equilateral triangle :
=》

where,
=》

=》

=》

or
=》

All you have to do is to solve this problem is 60+2+0.20+0.02
Answer:
The 85% onfidence interval for the population proportion of new car buyers who prefer foreign cars over domestic cars is (0.151, 0.205).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of
.
For this problem, we have that:
Sample of 421 new car buyers, 75 preferred foreign cars. So 
85% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
The lower limit of this interval is:

The upper limit of this interval is:

The 85% onfidence interval for the population proportion of new car buyers who prefer foreign cars over domestic cars is (0.151, 0.205).