<span> half life i= 78 hours
amount after 78 hours is 395 kg:
395 = 790e^(k*78)
Dividing by 790 and taking natural log
ln (395/790) = (k*78)
-0.6931 = 78k
-0.00888 = k
lets calculate how much is left after 18 hours:
Amount(18)
= 790e^(-0.00888*18)
Amount = 673.301 kg
hope this helps</span>
You did not include the choices. However, I answered one that just included them. I've included the possible answers below and then the correct answers.
<span>A multiple of Equation 1.
B. The sum of Equation 1 and Equation 2
C. An equation that replaces only the coefficient of x with the sum of the coefficients of x in Equation 1 and Equation 2.
D. An equation that replaces only the coefficient of y with the sum of the coefficients of y in Equation 1 and Equation 2.
E. The sum of a multiple of Equation 1 and Equation 2.
</span>A, B and E.
Adding and multiplying the terms allow them to keep working. However, you must make sure that each variable is changed each time. Not just one as in C and D.
Answer:
13 cm
Step-by-step explanation:
We can get the answer in the following way: