PROGRAMMING:Finding the product of even numbers between [1,10]
Find the product of even numbers between [1,10].
###Output format:
Output in the order of "t = result" in one line, output the result as is and keep six decimal places, no other additional format.
###Output example:
```out
t=3840.000000
```
answer：If there is no answer, please comment
###Output format:
Output in the order of "t = result" in one line, output the result as is and keep six decimal places, no other additional format.
###Output example:
```out
t=3840.000000
```
answer：If there is no answer, please comment