Can you arrange four 9's and use at most 2 math symbols, to make the total 100?

Spot 5 differences in two Christmas tree below:

What can you hold in your right hand, but never in your left hand?

Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

Can you solve the below algebraic mathematical equation?

(J+O+I+N+T)3 = JOINT

What goes through cities and fields, but never moves?

I was born in a small house and I live in it all alone. No windows and no doors have been assigned to my house. The only way I can go out is by breaking through the walls of my house.

Who am I?

If all the below statements are true

1. Gianni was either in Italy or France in 1997.
2. If Gianni did not kill Versace, Hilton must have killed him.
3. If Versace died of suffocation, then either Gianni killed him or Versace committed suicide.
4. If Gianni was in Italy in 1997, then Gianni did not kill Versace.
5. Versace died of suffocation, but he did not kill himself.

Who killed Versace and where was Gianni in 1997?

At my favorite fruit stand,
an orange costs 18,
a pineapple costs 27,
and a grape costs 15.
Using the same logic, can you tell how much a mango costs?

I am sure no one can have two things for dinner. what are they?