Questions

Can’t delete a row from primary table if there are related rows in secondary table.

A place where bees are kept is called as an apiary.

The compound with the molecular formula P4O10 is called Phosphorus pentoxide or tetraphosphorous decoxide. It is an anhydride of the Phosphoric acid.

A Disease which spreads by contact are Contagious.

Infectious diseases : These are caused by microscopic germs such as bacteria or viruses that get into the body and cause problems. Some but not all infectious diseases spread directly from one person to another. Infectious diseases that spread from person to person are said to be contagious. Some infections spread to people from an animal or insect, but are not contagious from another human. 

Contagious diseases such as the flu, colds, or strep throat spread from person to person in several ways. One way is through direct physical contact, like touching or kissing a person who has the infection. Another way is when an infectious microbe travels through the air after someone nearby sneezes or coughs.

Fatal Diseases : Diseases leading to failure or disaster.

Incurable Diseases : Diseases of a sick person not able to be cured.

The only gem of world made of a single element is Diamond.

Covalent bonds hold atoms together because the attraction between the positively charged nuclei and the negatively charged shared electrons is greater than the repulsions between the nuclei themselves.

Database provides necessary means to achieve this abstraction. By structure of a database we mean the data types, relations, and constraints that should hold on the data.