Answer:
87.5%
Step-by-step explanation:
to write a percentage as a number you move the decimal to the left 2 times.
Answer:
The function that represents the mass of the sample after t days is
.
The percentage rate of change per hour is of -2.46%.
Step-by-step explanation:
Exponential amount of decay:
The exponential amount of decay for an amount of a substance after t days is given by:

In which A(0) is the initial amount, and r is the decay rate, as a decimal.
Element X is a radioactive isotope such that its mass decreases by 59% every day. The experiments starts out with 390 grams of Element X.
This means, respectively, that 
So



The function that represents the mass of the sample after t days is
.
Hourly rate of change:
Decreases by 59% every day, which means that for 24 hours, the rate of change is of -59%. So
-59%/24 = -2.46%
The percentage rate of change per hour is of -2.46%.
Solve for y in the first equation.
Step-by-step explanation:
k² + 5k + 13 = 0
Using the quadratic formula which is

From the question
a = 1 , b = 5 , c = 13
So we have

<u>Separate the solutions</u>

The equation has complex roots
<u>Separate the real and imaginary parts</u>
We have the final answer as

Hope this helps you
The answer is D 105 because i know