1) A radioactive element, actinium, has a half-life of 4 seconds. You begin with 60 grams of actinium. a) Write an exponential equation describing the amount of actinium remaining after t seconds. [2 marks] b) How much actinium is remaining after 36 seconds. Round your answer to 2 decimal places. [2 marks] c) How long will it take for there to be 3.75 grams of actinium remaining. [3 marks] 2) List the transformation that have been applied to y = _%(7)'3X'9 + 4, if the base function is y = 7". [6 marks] 3) A bacterial culture grows exponentially. It starts with a population of 1,000 and grows to a population of 7,000 after 1 hour. a) Write an exponential equation for the population after t hours. [2 marks] b) What is the population after 180 minutes? [2 marks] b) How many hours will it take for the population to reach at least 300,000,000? [3 marks]