Answer:
<em>(a) 40 milligrams</em>
<em>(b) 1.21 milligrams</em>
Step-by-step explanation:
<u>Exponential Function</u>
It's commonly used to model real situations in life, like this one proposed in the question where the number of milligrams of a drug D(h) in a patient's bloodstream h hours after the drug is injected is modeled by the following function.

(a) The initial amount injected to the patient can be found when h=0

Initial amount: 40 milligrams
(b) Let's plug h=7
D(7) =40e^{-0.5(7)}=40e^{-3.5}=1.21
The amount in the bloodstream after 7 hours is 1.21 milligrams
Answer:
If the pool is 2/3 filled and then the inlet pipe and drain pipe are opened, it will take 140 hours to fill the pool
Step-by-step explanation:
An inlet pipe can fill the pool in hours = 20
Inlet pipe 1 hour work = 
A drain pipe can empty the pool in 21 hours
Drain pipe 1 hour work =
Inlet pipe and drain pipe 1 hour together work = 
Now we are given that the pool is 2/3 filled
So, remaining portion to be filled =
So, Inlet pipe and drain pipe fill
in hours = 1
So, they can fill 1/3 in hours = 
Hence If the pool is 2/3 filled and then the inlet pipe and drain pipe are opened, it will take 140 hours to fill the pool
(1/6 ft)/ (1/3 hour)= 1/2 ft/hour
The final answer is 1/2 ft/hour~
Answer:
1. $200 2. $150 3.$27
Step-by-step explanation:
1. 2,500 x .08 = 200
2. 2,000 x .075 = 150
3. 600 x .045 = 27
Answer:
teresas store
Step-by-step explanation: