Questions

The gas usually filled in the electric bulb is Nitrogen.

( int t ; t = a, a = b, b = t ;);

This code won't compile since declaration of t cannot occur within parentheses.

Settled agriculture was first seen in China around 6000 BC. The crops grown at this time were rice and millet.

Beginning in about 618 BC with classical millet agriculture, China's development of farming over the course of its history has played a key role in supporting the growth of what is now the largest population in the world.

They describe the details of how data is stored in the computers

The highly energetic gamma particles can penetrate most compounds that stop by other types of radiation. However, lead, steel, or concrete can reduce the high energy of these particles, making them less penetrating.

Hence, Gamma radiation can be stopped by a several inches of lead or steel, or several meters of concrete.