Answer:
Every hour, the medicine concentration decays by a factor of 4%.
Step-by-step explanation:
The relationship between the elapsed time, <em>t</em>, in minutes, since the medicine was ingested, and its concentration in the bloodstream, <em>C</em> (<em>t</em>), is:

The decay function is:

Here,
<em>y</em> = final amount
<em>a </em>= initial amount
<em>r</em> = decay rate
<em>t</em> = time
From the provided expression the decay rate is:

Thus, every hour, the medicine concentration decays by a factor of 4%.
0.813 is your answer because 7 is higher than 5 which means you have to round it up and not down
Answer:
i) There are 40320 possible orders
ii) There are 336 possible orders for the first 3 positions.
Step-by-step explanation:
Given: The number of finalists = 8
The number of boys = 3
The number of girls = 5
To find the number of sample point the sample space S for the number of possible orders, we need to find factorial of 8!
The number of possible orders = 8!
= 1 x 2 x 3 x 4 x 5 x 6 x 7 x 8
= 40320
ii) From all 8 finalist, we need to choose first 3 position. Here the order is important. So we use permutation.
nPr =
Here n = 8 and r = 3
Plug in n =8 and r = 3 in the above formula, we get
8P3 = 
= 
= 6.7.8
= 336
So there are 336 possible orders for the first 3 positions.