What does below rebus means ?

A kind heart person buy packed food at 3$/packet from United states and sells them at 1$/packet at Africa. After some time he becomes a millionaire.

How come the guy become millionaire ?

A new Engineering building containing 100 offices had just been completed. John was hired to paint the numbers 1 to 100 on the doors. How many times will John have to paint the number nine (9)?

Something Extraordinary happened on May 6th 19778 at 12:34am what was that?

A man and a dog were going down the street. The man rode, yet walked. What was the dog’s name?

How many points are there on the globe where, by walking one mile south, then one mile east and then one mile north, you would reach the place where you started?

Andrew’s doctor gives him three pills and tells him to take one every half hour. How much time will have passed by the time Andrew’s taken all three pills?

The person who makes it has no need for it. He who purchases it does not use it. The person who does use it does not know they are. What is it?

What is the value of 1/2 of 2/3 of 3/4 of 4/5 of 5/6 of 6/7 of 7/8 of 8/9 of 9/10 of 1000?

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