Atoms and Nuclei

A solution containing active cobalt $${^{60}_{27}}Co$$ having activity of $$0.8$$ $$\mu Ci$$ and decay constant $$\lambda$$ is injected in an animal's body. If $$1\,c{m^3}$$ of blood is drawn from the animal's body after $$10$$ hrs of injection, the activity found was $$300$$ decays per minute What is the volume of blood that is flowing in the body ? $$\left( {\,\,Ci = 3.7 \times {{10}^{10}}\,} \right.$$ decays per second and at $$t=10$$ hrs $$\left. {{e^{ - \lambda t}} = 0.84} \right)$$