Answer:
The substance half-life is of 4.98 days.
Step-by-step explanation:
Equation for an amount of a decaying substance:
The equation for the amount of a substance that decay exponentially has the following format:

In which k is the decay rate, as a decimal.
k-value of 0.1392.
This means that:

Find the substance's half life, in days.
This is t for which
. So







The substance half-life is of 4.98 days.
The 24 ounce one ig because if you divide 7.50 by 15 you’ll find out that it’s 0.50€ per ounce. You’re saving money and getting more for the 25 pack because it should originally be $12.50 but they are giving you 10 more ounces for just $11.75
Y = k/x where k is the constant of variation
y = 3 , x = 1.2 gives
3 = k/1.2
therefore
k = 3*1.2 = 3.6
and the required equation is
y = 3.6 / x
The formula for working out the total interior is:
180(n-2) = 1260
So let’s rearrange by dividing both sides by 180 and find what n is:
n-2 = 7
Then let’s add 2 to both sides to find what n is:
n=9
Each interior angle is 1260/9 = 140°.
The sum of the interior angle and its corresponding exterior angle is 180°.
Therefore, the polygon has 9 sides. :)