13+3k=11
-Move constant to the right-hand side and change its sign
3k=11-13
Calculate the difference
3k=-2
Divide both sides by 3
K= -2/3
Hello!
The answer is: 15 mL
Why?
From the statement we have that 250 mg need to be given every 8 hours, we can calculate how many mg will be given each day (24 hours):

So,
a day
We also know that there are 50 mg cefaclor every 1mL,
So, to know how many mL will be given with 750mg, we just need to divide it by 50

Therefore,
15mL or 750 mg of cefaclor will be given each day.
Have a nice day!
The Associative property of addition is being shown, because it doesn't matter the order of the terms.
It’s 7 over 69 but 420 for a short answer