What does this rebus means ?

PROG WORKRESS

Which is the correct shadow of the bird?

A man and a dog were going down the street. The man rode, yet walked. What was the dog’s name?

A word I know has six letters it contains, remove one letter and 12 remain. What is it?

You have two buckets - one holds exactly 5 gallons and the other 3 gallons. How can you measure 4 gallons of water into the 5 gallon bucket?

(Assume you have an unlimited supply of water and that there are no measurement markings of any kind on the buckets.)

A man who was outside in the rain without an umbrella or hat didn’t get a single hair on his head wet. Why?

What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see? What is it?

Two boys were admitted to a school. When the headmaster asks them about their parents, they tell him that they have same parents (father and mother). On further inquiry, it turns out that they both share the same date for their birthday.

"Are you twins," ask the headmaster.
"No," replies the boys.

Is it possible?

What does this rebus mean?

O
N
C
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TIME

In the Chess Board picture below white army is arranged. You need to add a black army on the board such that no piece is under any threat.
Note: Army comprised of 1 king, 1 queen, 2 rooks, 2 bishops, 2 knights, and 8 pawns.