What does this rebus means ?

PROG WORKRESS

You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?

If you’ve got me, you want to share me; if you share me, you haven’t kept me. What am I?

Can you find out which options fits best with the missing column?

I am the black child of a white father, a wingless bird, flying even to the clouds of heaven. I give birth to tears of mourning in pupils that meet me, even though there is no cause for grief, and at once on my birth, I am dissolved into air. What am I?

Take 9 from 6, 10 from 9, 50 from 40, and leave 6.

How Come ??

If you read clockwise, you can form a word by inserting three missing letters in the picture given below. Can you do it?

Imagine you are in a room with no windows or doors. How will you get out?

There are nine dots in the picture that has been attached with this question. Can you join all the dots by drawing four straight lines without picking up your pen?

Four cars come to a four-way stop, each coming from a different direction. They can’t decide who got there first, so they all go forward at the same time. All 4 cars go, but none crash into each other. How is this possible?