Answer:

Step-by-step explanation:
Greatest multiplier of 4 that is less than 21 is 5 (4 x 5 = 20)
Put the remaining number as the numerator (21 - 20 = 1)
Answer:
The concentration of a drug in an organ at any time t (in seconds) is given by s 0.25t - 15(1 - e-t/60) if osts 20 | 15e-t/60 – 10e-(t - 20)/60 if t> 20 where c(t) is measured in milligrams per cubic centimeter (mg/cm3). (a) What is the initial concentration of the drug in the organ? 0 mg/cm3 (b) What is the concentration of the drug in the organ after 14 sec? (Round your answer to three decimal places.) x mg/cm3 38 (c) What is the concentration of the drug in the organ after 40 sec? (Round your answer to three decimal places.) mg/cm3 Need Help? | Read It
Answer:

Step-by-step explanation:
In probability,
"AND" means "multiplication"
"OR" means "ADDITION"
We want probability of Blue Pen and Yellow Highlighter. So we find individual probabilities and "MULTIPLY" them.
Let P(b) be probability of blue pen
Let P(y) be probability of yellow highlighter
We know probability of event is that event divided by total number of that
So,
There are 4 + 2 = 6 pens
Blue pen = 2
Hence,
P(b) = 2/6 = 1/3
And,
There are 5 highlighters
Yellow highlighter = 1
Hence,
P(y) = 1/5
Now,
P(b and y) = 1/3 * 1/5 = 1/15
Hence,
probability of grabbing blue pen and a yellow highlighter is 
125-95=30
95-64=31
so it would be 125