1 bushel of soy beans = 60 lbs
1 bushel of corn = 56 lbs
1 metric ton of wheat = 37 bushels

to produce a barrel of oil from shale requires about 4.25 barrels of water,
(derived from NYT 5 Mar 74 story asserting that to produce 100,000 barrels
per year would require 20,000 acre feet per year)

Gosper algorithm for pi
c←5;b←8;r←1;
loop: c←4096c+(42r+5)b; b ← 8b ((2r+1)/(r+1))↑3; r ← r+1;
The approximation is 2↑(12r-8)/c.
Each trip around the loop gives 6r-1 bits.