Answer: a) 15, b) 1.
Step-by-step explanation:
A researcher studying public opinion of proposed social security changes obtains a simple random sample of 35 adult Americans and asks them whether or not they support the proposed changes. To say that the distribution of the sample proportion of adults who respond yes, is approximately normal, how many more Americans does the researcher need to sample in the following cases?
(a) 10% of all adult Americans support the changes
Here, 
And , 
So, consider the equality, to find the value of 'n'.

So, there are
more adult Americans needed.
(b) 15% of all adult Americans supports the changes
Here, 
So, again we get that

So, there are
more adult Americans needed.
Hence, a) 15, b) 1.
The explicit formula for given sequence is: 
Step-by-step explanation:
Given sequence is:
-1,4,-16,64.....
We can see that there is no same difference between consecutive terms so we will find common ratio to see if it is a geometric sequence.
Here

The explicit formula for geometric sequence is:

Putting the values of r and a1

Hence
The explicit formula for given sequence is: 
Keywords: Geometric sequence, common ratio
Learn more about geometric sequence at:
#learnwithBrainly
Answer: 3
3,000,000,000
Step-by-step explanation:
Billions have 9 zeros