N=NOe^-kt
N=mass at time t
NO = initial mass
k= 0.1476
t= time, in days
We are asked to find the half-life, which means you want to find how long it will take for half of the substance to decay/disappear (depending on situation).
If we are looking for half-life, we can simply set N to half of NO (which we are given a value of 40grams for)
Therefore:
N = 20
NO = 40
plugging these values and the value given for k back into the equation you get:
20 = 40e^-0.1476(t)
We are looking for t, so we have to manipulate the formula to get t by itself on one side of the equation.
We can start by dividing 40 from both sides, and you get:
0.5 = e^-0.1476(t)
We have the exponential function "e".
To get rid of e, we can use natural log (ln)
if e^y=x then ln (x) = y
look back at our equation we can set
0.5 = x
-0.1476(t) = y
Rewriting it in natural log form:
ln (0.5) = -0.1476(t)
Plug in ln (0.5) on a calculator to find its value and we get:
-0.693147 = -0.1476(t)
*Note: normally, getting a negative value would suggest that we did something wrong, because you cannot have a negative value as your t (you cannot have negative days), but because there is a negative on both sides of the equation, they will cancel out in this case.
The last step is to simply divide both sides by -0.1476
therefore:
T = 4.696119
But it asks you for the answer to the nearest tenth (one place after decimal pt) so
T (half life) = 4.7 days
Hope that helps :)
Answer:
180
Step-by-step explanation:
Nightly cost = x
x × 5% = Sales Tax
Total Cost : Percentage
189 : 105%
x : 100%
Cross multiply:
189 × 100% = 105% × x
189 = 1.05x
189 ÷ 1.05 = x
x = 180
<span>A) 1.5 percent.
And here's a quizlet link to help you
</span><span>https://quizlet.com/81564997/finn-3003-ch-17-flash-cards/
</span>
C(1)=6
c(2)=c(2-1)-16=c(1)-16=6-16=-10
c(3)=c(3-1)-16=c(2)-16=-10-16=-26
