A mechanic and a doctor:

A mechanic was removing the cylinder heads from the motor of a car when 
he spotted a famous heart surgeon in his shop that was standing off to the side, 
waiting for the service manager to come take a look at his car.
The mechanic shouted across the garage, "Hello Doctor! Please come over 
here for a minute." The famous surgeon, a bit surprised, walked over to the mechanic. 
The mechanic straightened up, wiped his hands on a rag and asked argumentatively, 
" So doctor, look at this. I also open hearts, take valves out, grind 'em, put in 
new parts, and when I finish this will work as a new one. So how come you get the 
big money, when you and me are doing basically the same work?". 

The doctor leaned over and whispered to the mechanic
"Try to do it when the engine is running."

Do you know !!!

When examining planets in our solar system, we usually find characteristics shared by multiple planets. Taking this into account, how many planets in our solar system have earthquakes?