Answer:
- Question 1:

- Question 2:

- Question 3:

- Question 4:

Step-by-step explanation:
Question 1: Write down the differential equation the mass of the bacteria, m, satisfies: m′= .2m
a) By definition:

b) Given:

c) By substitution:

Question 2: Find the general solution of this equation. Use A as a constant of integration.
a) Separate variables

b) Integrate


c) Antilogarithm



Question 3. Which particular solution matches the additional information?
Use the measured rate of 4 grams per hour after 3 hours

First, find the mass at t = 3 hours

Now substitute in the general solution of the differential equation, to find A:

Round A to 1 significant figure:
Particular solution:

Question 4. What was the mass of the bacteria at time =0?
Substitute t = 0 in the equation of the particular solution:
