People make me, save me, change me, raise me. What am I?

Today is John's birthday.
A year ago, John had five candles and he lit all the candles except the one at the last.
Now he is going to light all the candles.

How old is John Today?

(He is not five today.....)

A wooden log balances equally on the scales when weighed with three-quarters of a pound and three-quarters of a wooden log.

Can you calculate the weight of the entire wooden log?

You need to arrange three 7 and mathematical symbols to form number 1?

Why is 6 afraid of 7?

Below rebus represent famous DiCaprio movie. Can you name it?

A man was driving a black truck. His lights were not on. The moon was not out. A lady was crossing the street. How did the man see her?

What do you answer even though it never asks you questions?

Accidentally, two trains are running in the opposite direction and enter a tunnel that is 200 miles long. A supersonic bird that has fled the lab and taken shelter in the tunnel starts flying from one train towards the other at a speed of 1000 mph. As soon as it reaches the second train, he starts flying back to avoid collision and meets the first train again at the other end. The bird keeps flying to and fro till the trains collide with each other.

What is the total distance that the supersonic bird has traveled till the trains collided?

Can you count the number of lines in the below picture?