Answer: aA 90% confidence interval for the population proportion of adults in the U.S. who have donated blood in the past two years = (0.163,0.189)
Step-by-step explanation:
Let p = population proportion of adults in the U.S. who have donated blood in the past two years.
Given: A Gallup survey of 2322 adults (at least 18 years old) in the U.S. found that 408 of them have donated blood in the past two years.
Sample size: n= 2322
Sample proportion 
Critical z-value for 90% confidence level : z*=1.645
The confidence interval for population proportion:

A 90% confidence interval for the population proportion of adults in the U.S. who have donated blood in the past two years:

Hence,
Anything except pi is a rational number. So 9 and 7/10 is one or it could be a whole number
<span>The resent value, also called "discounted value," is the current worth of the camera. So, we know that the discounted value is $105.00.
The first price of the camera was $120.00.
This means that the price is decreased. In order to calculate the discount rate we should find out how many percent the camera was discounted. 105 from 120 is: 105/120*100=87.5
So, the discount is 100-87.5=12.5 %.
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There is not enough information
Answer:
A.
Step-by-step explanation:
A. City voters were asked about candidates. That seems to be random.
B. A survey about singers took place at a specific concert. Naturally, the people who are there like this singer. It is not random.
C. Customers were asked about food at a pizza shop. Naturally, they like pizza. This is not random.
D. An email survey was sent. Mostly people who own computers will respond. This is not random.
Answer: A.