MATH 16A QUIZ 6-
(1) A sample of radioactive material disintegrates from 25000 grams to 10000 grams in 12 days. After how many days will 256 grams remain?
(2) Let A(t) be the balance in a savings account after t years, and suppose that A(t) satisfies the differential equation
A'(t) = (ln 3)A(t)
with initial condition A(0) = 2.
(a) Find the formula for A(t).
(b) What is the balance at t = 3?
(c) At which time t is the balance equal to 162? Simplify your answer (it should be a whole number).