What does the below rebus riddle means?

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

There are nine dots in the picture that has been attached with this question. Can you join all the dots by drawing four straight lines without picking up your pen?

Solve the equation by replacing the alphabet with numbers.

MOM + MOM + NO = BOOK=

I make a loud sound when I’m changing. When I do change, I get bigger but weigh less. What am I?

You have four chains. Each chain has three links in it. Although it is difficult to cut the links, you wish to make a single loop with all 12 links. What is the fewest number of cuts you must make to accomplish this task?

It walks on 4 when its young, walks on 2 when it's older, and walks on 3 when its very old?

On a windy rainy night , I was driving in my car.
When i reach the bus stand , i see three people waiting for the bus.

1. An old lady who needs an immediate medical attention
2. My Best Friend
3. Girl whom i love from childhood

My car is a two seat, so can you tell me , what i have done in this situation ?

Forwards I am heavy, backward I am not. What am I?

What can run but never walks, has a mouth but never talks, has a head but never weeps, has a bed but never sleeps?