Answer:
The answer is C(x) = 60x + 14 and the answer to the second one is 7 days.
Step-by-step explanation:
C(x) =60x + 14
434 = 60x + 14
-14 -14
420 = 60x
/60 /60
7 = x
or
x = 7 days
Answer:
1.5625
Step-by-step explanation:
Answer: 4 years
Step-by-step explanation:
A(0) has to be amount at start. Assume that's 5mg
Then A(t) = 5×(0.5)^(0.25t) = 5×2^(-t/4),
(also known as 5 exp(-λ t) with λ = ln(2)/4, incidentally).
We need to such that A(t) = 2.5mg, or 2^(-t/4) is 1/2, which happens when -t/4 is -1, or t is 4.
One meter is 3.28 feet, so anything shorter than that. A basketball, maybe a very young child?
