Answer:
(b) 26.6 days
Step-by-step explanation:
Half life, T = 4 days
initial amount, No = 100 mg
(a) The exponential function is given by
[tex]N = No e^{-\lambda t}\\\\N = No e^{\frac{-0.693t}{T}}\\\\N = No e^{\frac{-0.693t}{4}}\\\\N = No e^{\frac{-0.17325t}{T}}\\\\[/tex]
where, N is the amount left.
(b) N = 1 mg
[tex]N = No e^{\frac{-0.17325t}{4}}\\\\1 = 100 e^{\frac{-0.17325t}{4}}\\\\4.605 = 0.17325 t \\\\t=26.6 days[/tex]
