grains

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 19​?
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.)

How many grains of wheat should be placed on square 19​? _____grains

How many total grains of wheat should be on the board after the the grains of wheat have been placed on square 19​? _____grains

What is the total weight of all the grains of wheat on the board after the grains of wheat have been placed on square 19?_____ Pounds
​(Round to the nearest tenth as​ needed.)