A king in ancient times agreed to reward the inventor of chess with one grain of wheat on the first of the 64 squares of a chess board. on the second square the king would place two grains of​ wheat, on the third​ square, four grains of​ wheat, and on the fourth square eight grains of wheat. if the amount of wheat is doubled in this way on each of the remaining​ squares, how many grains of wheat should be placed on square 16​? also find the total number of grains of wheat on the board at this time and their total weight in pounds.​ (assume that each grain of wheat weighs​ 1/7000 pound.)