What does an Island and the letter T have in common?

By including only four matchsticks in below picture, you have to make "Four Triangles And Two Squares"

Here is a mathematical expression that also secretly tells a movie name. What movie is that?

If two's company, and three's a crowd, then whats four and five ?

Why are televisions attracted to people?

To attend world science seminar, A famous chemist from Mexico visit
London. In the lab, the scientist was killed and his six assistants were under suspicion of killing the chemist.
Name of six assistants: Austin, Wayne, Dege, Oscaru, Lingard, and Rojo.
He left a note "76-20-44 79-16-22-7"

A local detective Jack was called to solve the case,

After reading the note, Jack instantly asked the police to arrest the murderers.

Who are the murderers?

What is always in front of you but can’t be seen?

John went to meet his friend Jacob, but when he was about to reach the main gate, John notices that Jacob had a mighty dog who was fastened to the tree. The chain is long enough that it allows the dog to reach the main gate.

How can the John reach the main gate?

Buy me, smell me or deliver me, I do not change.

Who am I?

I have branches, but no fruit, trunk or leaves. What am I?