What does this rebus puzzle means ?

What can you serve, but never eat?

A woman named Maria was at the funeral of her mother. She met a nice young man that she had never seen before and after the service, they spent a bit of time together. Then she got busy and didn’t get his name or phone number before he left. She tried to find him, but no one knew who he was or how to contact him. A few weeks later, Maria’s older sister dies and the police suspect murder. Who killed the sister?

Decode below rebus
D
N
A
T
S , D

You are in a room with no metal objects except for two iron rods. Only one of them is a magnet.
How can you identify which one is a magnet?

What is the next number?

77, 49, 36, 18 ?

Imagine you are in a room with no windows or doors. How will you get out?

Prove that the below maths equation is true.

8 + 8 = 91

What is in seasons, seconds, centuries and minutes but not in decades, years or days?

You can hear me, but you can't touch or see me.

What am I?