Questions

Force of impact is the force when the objects meet. The speed of the object plays an important role in the generation of force of impact. The laws of physics determine that the force of impact increases with the square of the increase in speed.

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

DOZENS.

If we remove 'S' from it, it is DOZEN which tells that 12.

I am ABBREVIATION that make things short but I am pretty long myself.

Example ::

HIV - Human Immuno Virus

WHO - World Health Organization

China has been by far the biggest coal producing country over the last three decades. The country produced about 3.6 billion tonnes (Bt) of coal in 2012 accounting for over 47% of the world's total coal output.

The atmosphere is a mixture of several gases. Nitrogen is the most abundant gas in the atmoshere and oxygen is next to it. It is 78% in the atmosphere and 21% is oxygen. Remaining 1% is all other gases like argon, hydrogen, neon, etc...

11

Because, on preprocessing the expression becomes  a = ( 3 + 2 * 2 + 3),  as Ist preference is multiply & then addition, it evalvates as(3+ 2 * 3 +2) = (3+6+2)=11.