Answer:
200 students must agree to attend in order for the school to have the festival.
Step-by-step explanation:
200 is 40% of 500. We can also use fractions to figure this out.
For 100 to become 500 it must be multiplied by 5. And whatever we do to the denominator we have to do to the numerator. So we multiply 40 × 5 = <em>x</em>
<em>x</em> = 200
Answer: A)
B) H = 5.10
C) Yes
Step-by-step explanation: <u>Exponential</u> <u>Decay</u> <u>function</u> is a model that describes the reducing of an amount by a constant rate over time. Generally, it is written in the form:
A) C is initial quantity, in this case, the initial concentration of DDT. To determine r, using the data given:
Using a natural logarithm property called <em>power rule:</em>
The decay function for concentration of DDT through the years is
B) The value of H is calculated by
Again, using power rule for logarithm:
H = 5.10
Constant H in the half-life formula is H=5.10
C) Using model to determine concentration of DDT in 1995:
y(24) = 0.5
By 1995, the concentration of DDT is 0.5 ppm, so using this model is possible to reduce such amount and more of DDT.