Answer:
The standard error of the proportion is 0.112.
Step-by-step explanation:
The standard error of a proportion is given by the following formula:

In which p is the probability of a success and n is the length of the sample.
In this problem
A success is a student defining themselves regular dietary supplement users. Our of 3000 students, 1500 do. So
.
We take a sample of 20 of them, so
.
So

A scale map is not an actucal size its a small size we can see
Answer: 40000
Step-by-step explanation:
The formula to find the sample size is given by :-
, where p is the prior estimate of the population proportion.
Here we can see that the sample size is inversely proportion withe square of margin of error.
i.e. 
By the equation inverse variation, we have

Given :


Then, we have

Hence, the sample size will now have to be 4000.
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Answer:</h2><h2>51.</h2>
Hope this will help you lot.