The half-life of an isotope is the time for its mass to decay by 2. For example, polonium-210 has a half-life of 40. So, a sample of 100 g would decay to 50 g in 40 weeks. The percent, P, of polonium remaining after t weeks is given by the formula P = 100 * (0.5) ^ (1/40) . What percent, to the hundredth of a percent, of polonium remains after 30 weeks?