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. 

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.