Biomedical engineers are developing an insulin pump for diabetics. To do this, it is important to understand how insulin is cleared from the body after a meal. The concentration of insulin at any time t is described by the equation

C = C₀ e^-30t/m

where C₀ is the initial concentration of insulin, t is the time in minutes, and m is the mass of the person in kilograms. Use solve to determine for a person whose mass is 65 kg how long it will take an initial concentration of 90 to reduce to 10. Use double to get your result in minutes.