3 people know a fact in 1st day.
In 2nd day they share it with 3 people each=3×3
Now 3×3 people shares it with 3 people each. and so on...
So,
3+3²+3³+3⁴+3^5+3^6+3^7
=3279 no of people altogether , will hear from 1st day to 7th day...
On the day 7,no of people who will hear the fact=3^7=2187
Answer: 
This is the same as saying 18*sqrt(2) or you could say 18√2
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Explanation:
We'll be using this square root rule: 
So we could have this as our steps:

Therefore, 
The basic idea is to first combine the roots using that rule. From there, we factor the radicand such that we pull out the largest perfect square factor. This will allow us to break the root apart and fully simplify it.
The answer is B becuase if u take the reciplericle by the antiretroviral you would get B
make a graph and put the weeks and the change wich is -20 a day until the end of the four weeks
:every week 4 the city gets -20 degrees celsius colder. This means that every 4 weeks the tempature decreases then goes bac kto its origonal