PC12 cells produce dopamine and so they may be useful in treating Parkinson’s disease (when dopamine is missing). One approach would be to encapsulate PC12 cells inside a spherical capsule (400um in outer diameter (OD); 25 um wall thickness) and then implant these capsules inside the brain. The capsules serve to protect the cells from the brain of the recipient. Under one set of circumstances, the cell density in the capsules is initially 1 x 106 cells /mL and the capsules are incubated in vitro until enough cells grow up to fill up the entire capsule. Calculate the necessary incubation time for 50 capsules to produce enough dopamine for a mouse. The doubling time of a PC12 cells is 8 hours. Assume the kinetics of cell growth are the same as the problem above. Data given: Mass of the mouse: 250 g; Ratio of mouse head mass to overall mass: 1/10; Ratio of mouse brain mass to head mass: 1/5; Dopamine secretion in vitro: 1 g/10^7 cells/day; Initial encapsulation cell density: 1×10^6 PC12 cells/mL; Dopamine requirement: 0.1 g/kg brain mass/day.