Questions

Nuclear Force

I am black gold i.e charcoal. It is black when it is not used and when using it is red due to fire and when used it is in grey color as it becomes ash. 

Coal is chemically complex fuel. Whenever it is burned, gases are given off and particles of ash, called "fly ash," are released. Release of sulfur from burning into the air. The sulfur in coal combines with oxygen to form sulfur dioxide, which can be a major source of air pollution if emitted in large enough quantities. This stuff comes back as acid rain when it attaches itself to a raindrop. 

Today, many of the effects of coal burning have been reduced significantly or eliminated. This is super-nasty and is only stopped by buying low-sulfur coal from Montana or Wyoming. The eastern power plants have to pay to move the coal from out west and this increases the price of power production.

The prime cost calculates the use of raw materials and direct labor, but does not factor in indirect expenses, such as advertising and administrative costs.

Supervisor's wages doesn;t come under prime cost.

"The moon smiled at me" is the example of personification in the given options.

Personification is a technique in which we give objects human traits like emotions, gestures, speech,... by using metaphor. 

Here moon is an object which cannot smile but using metaphor sense, we gave that sense to it.

Right ventricle (which pumps blood to the lungs), pulmonary artery (which carries blood to the lungs), and left atrium (which receives blood from the lungs) are involved directly in pulmonary circulation.