What is always in front of you but can’t be seen?

Two prisoners Jack and Jill are locked in a cell.
There is open window approx 40 feet above the ground of the cell.
They are never able to reach there.

Then they plan to escape by a tunnel and they start digging out.
After digging for more than 20 days, Jill comes with the different plan and they escaped.

what was the plan ?

I am quite hot but become too cold if you remove the first two letters. What am I?

Can you solve the photo plexer logic ?

There is an English word that can be used up to four times in a row without modifying the spelling and form a valid grammatical sentence.

Do you know what word is that?

The centre of the third figure is empty. What digit should fit inside?

Take away the whole and some still remain. What is it?

After teaching his class all about Roman numerals (X = 10, IX=9 and so on) the teacher asked his class to draw a single continuous line and turn IX into 6. The teacher's only stipulation was that the pen could not be lifted from the paper until the line was complete.

What seven-letter word has hundreds of letters in it?

What is full of holes but still holds water?