To answer this item, we formulate an equation that would relate the time, rate, and the final time.
A(t) = (Ao)(2)^(t/4)
We solve for the value of Ao by substituting the known values,
11 = (Ao)(2)^(50/4)
Ao = 1.89 x 10^-3
A quarter of 11 is 11/4. Using this value and the other known.
11/4 = (1.89 x 10^-3)(2)^(t/4)
The value of t from the equation is 42 minutes.
