The population of a species of bird has been decreasing in a particular region of the desert. In 2015, the population was k . In each case below, write an equation for the population as a function of time t, the number of years since 2015. (a) The population decreases by 50 individuals every two years. OP (t ) = k - (t+ 25) O P(t) = k(1 - 50t) OP(t ) = k - 50t O P(t) = k(1 - 25t) OP(t ) = k - 25t (b) The population decreases by 4 % each year. O P (t ) = k (0.96 ) t OP(t) = k(4)-t-2015 O P(t) = k(0.96)t-2015 OP ( t ) = k + k (0.96)t OP ( t ) = k ( 4 ) - t