suppose that the world’s current oil reserves is R= 2150 billion barrels. If, on average, the total reserves is decreasing by 20 billion barrels of oil each year answer the following: A). give a Linear equation for the total remaining oil reserves, R, in billions of barrels, in terms of T, the number of years since now. B.) seven years from now, the total oil reserves will be __blank__ billions of barrels. C). if no other oil is deposited into the reserves, the worlds oil reserves will be completely depleted (all used up) approximately __blank__ years from now. (round your answer to two decimal places)