Can you fill the blank with the correct number?

6 30 870 756030 _____

What are the next two letters in the following series and why?
W A T N T L I T F S _ _

*Hint: Check Puzzle Title

You have a roll of cloth 1km long. You have a machine which cuts this roll into pieces of 10-meter-long cloth.

How long would it take for the machine to cut the roll if each cut took 4 secs?

There is a box full of marbles,
all but two are blue,
all but two are green,
and all but two are red.

How many marbles are in the box?

What is the word or phrase below?
R | E | A | D

Can you think of a smallest +ve number such that if we shuffle the digits of the number, the new number becomes double the original number?

Using eight eights and addition only, can you make 1000?

Luis Garavito killed Density x Volume.

Who is Luis Garavito ?

Three friends named Mr. Black, Mr. Yellow and Mr. Green enter a pub on a weekend night. They are wearing either a Black, Yellow or Green shirt.

Mr. Yellow says to them, 'Did you notice that we all are wearing different color shirts than our names?'

To this, the man who was wearing the Green shirt said. 'Wow, thats right.'

Can you identify who is wearing which colour shirt ?

Can you name any English verb that becomes its past tense by simply rearranging the alphabets ?