Answer:
-Exponential Decay
-Decay factor is (1-0.05)
Step-by-step explanation:
-Given that the number decreases by a defined rate each year from the initial size by 5%,
-This is an exponential decay function of the form:

Where:
is the quantity/size after time t
is the initial size
is the rate of decay
-Our function can the be written as

Hence, the decay rate/factor is 0.05
#Alternatively
The exponential decay can be of the form:

Where:
y is the size at time x, a is the initial size, x is time and b is the decay factor.
b is of the form 

Hence, the decay factor is (1-0.05)
The answer is -4.5
To solve these types of problems it's best to work backwards.
-2 - 16 = -18
4 x (n) = -18
n = -18/4
n = -4.5
1. 84 = 1 x 84
2. 84 = 2 x 42
3. 84 = 3 x 28
4. 84 = 4 x 21
5. 84 = 6 x 14
6. 85 = 7 x 12
Hope this helps!
Answer:
10 hours
Step-by-step explanation:
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