A radioactive substance has a mass of 140 g at 3 p.m. and 100 g at 8 p. m. Write an equation in the form of A = Ao that models this situation, where h is the constant representing the number of hours in the half-life, Ag is the initial mass, and A is the mass t hours after 3 p.m. Using this equation, solve for h, to the nearest ten thousandth. Determine when the mass of the radioactive substance will be 40g. Round the answer to the nearest tenth of an hour. - aSo/ve gives an error must show the algebraic solution.
