Final answer:
The starting value (a) is 34.3, the growth factor (b) is 0.788, and the growth rate (r), expressed as a percentage, is -21.2%. This represents a decay rate rather than a growth rate. Option b is the correct answer.
Step-by-step explanation:
The question requires us to identify the starting value a, growth factor b, and the growth rate r from the given exponential function Q = 34.3 (0.788)^t. Comparing it to the general form Q = ab^t = a(1 + r)^t it's clear that:
- The starting value a is 34.3,
- The growth factor b is 0.788.
To find the growth rate as a percent, we need to express b as 1 + r. So, 0.788 = 1 + r, which means r = -0.212 (since it's negative, this is actually a decay rate).
Converting the decimal to a percentage, r as a percent is -21.2%.
Therefore, the correct answer is:
- a = 34.3,
- b = 0.788,
- r = -21.2%.