Only one color, but not one size,
Stuck at the bottom, yet easily flies.
Present in sun, but not in rain,
Doing no harm, and feeling no pain.
What is it?

Which is faster, Heat or Cold ? Explain.

A boy and a girl are sitting on the porch.
"I'm a boy," says the child with black hair.
"I'm a girl," says the child with red hair.
If at least one of them is lying, who is which?

How can you make number one disappear by adding something to it?

If you remove one from eleven, it becomes ten. If you remove one from nine, it becomes ten.

How is this possible?

In a science lab, a petri dish hosts a healthy colony of yeast for an experiment. Now every minute, all the yeast cells divide into two. At noon, there was just a single cell of yeast and at 1:22, the Petri dish was half full. Can you calculate when the dish will be full of yeast?

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?

It has a long neck, A name of a bird, Feeds on cargo of ships, It's not alive,

What is it?

What does below Rebus say?

XLR8

Four people need to cross a rickety bridge at night. Unfortunately, they have only one torch and the bridge is too dangerous to cross without one. The bridge is only strong enough to support two people at a time. Not all people take the same time to cross the bridge. Times for each person: 1 min, 2 mins, 7 mins and 10 mins. What is the shortest time needed for all four of them to cross the bridge?