We have events:

- a <span>student stays in the school's dormitory

- </span>a <span>student stays with family

- </span><span>a student receives As
and </span> probabilities:

We want to calculate the probability <span>that the student lives in the school dormitory given he </span><span>receives As so it will be </span>

. From the <span>Bayes' theorem we know that:

The only thing we don't know is

, but we can calculate it using the l</span><span>aw of total probability. There will be:

So our probability:

Answer D.
</span>
To double you have to multiply by 2.
13×2=26
I believe it’s 6 g/cm3. I hope this helps!
51 Divide what's in the ( ) then add the 3
If the negative square root is found to be one of your solutions, then that is indicative of a pair of imaginary roots (the imaginary i). According to the conjugate rule, if you have one solution that is imaginary, you will have another but with the opposite sign. For example, if a solution to a quadratic is found to be 2 - i, then its conjugate, 2 + i is also a solution. They will ALWAYS go in pairs. Same thing with radical solutions. If one solution is found to be 
then
will also be a solution.