Questions

Electronic Flash differs from the consumable bulb flash in important aspects. Instead of creating light by burning up in an atmosphere containing oxygen, a consumable material (each bulb being used therefore only once), it produces a brilliant incandescent by discharging a current for a brief instant through a rarified gas, usually xenon. The gas glows every time the discharge is made through it but it is not consumed, so that many thousands of flashes are obtainable from a single tube, which helps to offset the much higher cost of the initial apparatus.

A promise. 

The Promise made to somebody by you can be break but you cannot touch it.

The classical orchestra uses violin, flute, clarinet, cello, piccolo, Bass,...

Ayer's Rock

The first wholly artificial gene was synthesized by Har Gobind Khorana.

All enzymes are proteins but all proteins are not enzymes since, enzymes are subset of proteins.