A car operates at maximum economy, gas-wise, at speeds between 25 and 35 miles per hour.
-4
An airplane mechanic invented Slinky while he was playing with engine parts and realized the possible secondary use for the springs.
12
The first alarm clock could only ring at 4 a.m.
120
Surgeons who grew up playing video games make 37 percent fewer mistakes.
250
Sony researchers have developed a refrigerator that only opens when you smile.
9
The first hard drive available for the Apple II had a capacity of only 5 megabytes.
46
A small airplane can fly backwards.
75
Attics were invented in Attica.
43
