4.कमपयुटर हारडवेयर तिन परकारमा विभाजित छ। तिनीहरू हुन :

Compounds with hydrogen bonding tend to have higher melting and boiling points because the hydrogen bonding leads to stronger intermolecular forces. Intermolecular forces are the attractive forces between molecules, and they affect the physical properties of a substance, including melting and boiling points.

Hydrogen bonding is a particularly strong type of intermolecular force that occurs when a hydrogen atom is bonded to a highly electronegative atom such as nitrogen, oxygen, or fluorine....

At the bottom-is the correct one.

Riemann's green is a green pigment ZnO.CoO, which is obtained by heating a mixture of zinc oxide and cobalt nitrate or by the reaction of cobalt nitrate with either 3Zn(OH)2ZnCO3 or zinc sulphate.