What four weights can be used to balance from 1 to 30 pounds?

With pointed fangs I sit and wait; with piercing force I crunch out fate; grabbing victims, proclaiming might; physically joining with a single bite. What am I?

I am a five-letter word and people eat me. If you remove the first letter I become an energy form. If you remove the first two letters, I am needed to live. Scramble the last three letters and I am a drink. What word am I?

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

How is a fly different from a mosquito?

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?

I want to fill my bucket using both cold and hot water.
I have two taps for both cold and hot water. The hot water tap fills the bucket in exact 6 hours and the cold water tap fills the bucket in exact 4 hours.
I turn both of them simultaneously but I forgot to turn off another tap which removes the water out of the bucket. This tap can empty the bucket in 12 hours.

How Long will it take to fill the bucket?

What is the four-digit number in which the first digit is one-third the second, the third is the sum of the first two, and the last is three times the second?

what does this picture(rebus) riddle means ?

Which of the following words don't belong in the group and why?
CORSET, COSTER, SECTOR, ESCORT, COURTS