Mystery Solve....

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My keyboard battery is really dying....

You dun have to tell me about Xai Ming one....
Awwwwwww... Typo... is Xiao Ming...

Oh well... Who cares

So let analyze the question together...
OK with myself
Seem you there only need to read...

Xiao Ming was shot to death while in his car. There were no powder marks on his clothing, which indicated that the gunman was outside the car. However, all the windows were up and the doors locked. After a close inspection was made, the only bullet-holes discovered were on his body.

Xiao Ming was shot to death while in his car.
OK from here we know that Xiao Ming was shot.

There were no powder marks on his clothing, which indicated that the gunman was outside the car.
Here we know that Xiao Ming was in his car when his was shot and got killed, not only that we also know that the gunman wasn't in the car when the gun was fired.

However, all the windows were up and the doors locked.
Door are locked and windows were up... Erm...
This shows that Xiao Ming got shot after he enter his car and locked the door.
So we now know that the gunman didn't open the door to shoot Xiao Ming and did not shoot through the window.

After a close inspection was made, the only bullet-holes discovered were on his body.
Arg... So only the body has hole...
This should answer the question about shooting through the door...

So let put all the facts together...
Xiao Ming was in his car, which has all the doors locks and all windows up.
The gunman not only shoot Xiao Ming from outside the car, the gunman also manage to create a bullet hole ONLY on Xiao Ming's body...

From this... and thinking from other view...
We can firmly say that Xiao Ming is driving a convertible cars.
That will explain how he got shot when he is in a enclose space.
So we now can say the gunman shot Xiao Ming when his car roof was still kept, then close the roof after killing Xiao Ming.

So let answer the question together...

How was Xiao Ming killed?

To be honest... The analyzing wasn't that hard right?
The only hard part about this question is the question itself...
It is a trick question to being with...

Still don't get it?
Well the answer was given to you all right at the start if you read the whole thing carefully.

How was Xiao Ming killed?
It is asking how he got killed...
The answer is...
He was shot to death