Which shortcut key is used to switch between two open applications?

A person interested in collecting, studying and selling of old things .

Choose the word which is the nearest opposite to the meaning of the bold word:

I wish I could pursue my studies.

simultaneously

Select the most appropriate synonym of the given word

Zealous

Select the most appropriate meaning of the given idiom. "Go down like a lead balloon"

Someone who is self-employed and hired to work for different companies on particular assignments.

Select the INCORRECTLY spelt word.

Choose the option that is similar to the word given below

REPULSIVE