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,
65
1. you work in the parentheses and multiply 2.8 by 5 which is 14
2. you divide 14 by 7 which is 2
3. you follow PEMDAS and multiply 26 by what is in the parentheses (2) which is 52
4. you add 13 with 52 which is 65
hope this helped!!
<u>Answer:</u>
C. Left-handed: 48, Right-handed: 504
D. Left-handed: 30, Right-handed: 315
<u>Step-by-step explanation:</u>
We are given that there are 58 left-handed students and 609 right-handed students at East Middle School and these numbers of students are proportional to the number of left and right handed students at East Middle School.
Given the above information, we are are to determine which two options could be the the numbers of left-handed and right-handed students at West Junior High.
Ratio of right handed to left handed students at East Middle School = 
Checking for ratios of the given options:
A. 
B. 
C. 
D. 
E. 
Therefore, the possible numbers of left-handed and right-handed students at West Junior High could be C. Left-handed: 48, Right-handed: 504 and D. Left-handed: 30, Right-handed: 315.
Lines 2 & 3 are parallel.
R=7s/3+k/3
Hope this helps!