A 36-g mouse is to be injected with 32P (half-life = 14.3 d; average beta energy= 0.70 MeV; no gamma). Assume that the 32P distributes itself almost instantaneously throughout the body following injection and that none is lost from the body for the first few hours thereafter. What activity of 32P needs to be administered in order to give the mouse a dose of 10 mGy in the first hour? Give all assumption(s) that you make.