The total world population is forecast to beP(t) = 0.00078+ -0.0715t +0.89t + 6.04 (0 ?ts 10)in time t, where t is measured in decades,

The total world population is forecast to beP(t) = 0.00078+³ -0.0715t² +0.89t + 6.04 (0 ?ts 10)in time t, where t is measured in decades, with t= 0 corresponding to 2000 and P(t) is measured in billions.(a) When is the total world population forecast to peak? In what year? You MUST justify that your result is an optimal value.t =(Round your answer down to the nearest tenth.)The corresponding year is. (Round your answer down to the nearest year.)(b) At what number will the population peak? (Round your answer to two decimal places.)billion