Answer:
less than 17 minutes
Step-by-step explanation:
If the half-life is t, then every t days, the amount of the radioactive isotope will be cut in half.
(1/2)^(number of half-lives) = 3%
number of half-lives = ln(0.03) / ln(0.5)
This gives the number of half-lives as 5.06.
Then 300 days = (5.06)(length of 1 half-life)
length of 1 half-life = 300 / 5.06 = 59.29 days
Answer:
V = 4.187r³
Step-by-step explanation:
Volume of a sphere is expressed using the formula;
V = 4/3πr³
r is the radius
Substitute π = 3.14 into the formula
V = 4/3 * 3.14r³
V = 4.187r³
Hence the volume of a sphere in terms of the radius is V = 4.187r³
Answer:
R + 5b = 300
Step-by-step explanation:
Rogers steps include a scale holding five bricks of equal weight and the scale reads 300 pounds.
We want to write an equation relating Rogers weight and the weight of the bricks to the total weight of the bricks to the total weight shown on the scale.
We have been told to use R for Rogers weight and b for the weight of a single brick.
Since Rogers is holding 5 bricks, the weight of 5 bricks will be 5b.
The sum of Rogers weight and the five bricks is equal to 300 pounds.
Therefore, the equation relating them is:
R + 5b = 300
