Invented by Everready division of Union Carbide (now no more)
Lew Urry invented it in Cleveland
Today's batteries have 40x the capacity of the original.
**Typical US household owns 18 battery-powered devices.
Also: US drivers put on 2.4 trillion passenger-miles last year.
Doubled in last 15(?) years. That is to say, just under 10,000 miles
per person per year, or 30 miles per person per day!
This also can be used to calculate retail gasoline sales
(conservatively, 120 billion gallons, a $150B industry). The question
is, can you derive the number of retail gas stations?
A: almost half a million -- that is to say, 240,000 gallons per
station per year. Working backwards, that's about, say, 660 gallons
per day, or with only 55 customers per day. Hmm. That seems way too
low... or is the average transaction size noticeably smaller than 12
gallons?
Rohit