What is so fragile that saying its name breaks it?

Can you find out which number multiplied by itself will give the output as 12345678987654321?

Can you arrange the six given marbles in a manner that each one of them is touching all four marbles of different colours?

What word does this rebus represent?

meta meta
meta meta

Without looking at a calendar, within a minute name, a boy's name using 5 consecutive 1st letters of 5 consecutive months

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

I’m tall when I’m young, and I’m short when I’m old. What am I?

My friends called me Iron59 because my parents are a chemist and a mathematician. What is my real name?

I can turn polar bears white.
I can make anyone dance.
I can make everyone cry
I can make your hands clap
I can make you thin.
I can make you smile.
I can make you smile

Can you guess the riddle?

Two guards were on duty outside a barracks. One faced up the road to watch for anyone approaching from the North. The other looked down the road to see if anyone approached from the South. Suddenly one of them said to the other, "Why are you smiling?"

How did he know his companion was smiling?