How can I check if a process is running from a batch/cmd file? And If process is running, how do I stop the process automatically?

Like a cmd script thingy, can someone give me some hints or help me make that kind of script.

Example (pseudo code):

```
If calc.exe is running                        
Stop calc.exe

```

I want something like this:

```
@echo off

:x  
PATH=C:\Windows\System32\calc.exe  
If calc.exe is ON goto Process_Stop

:Process_Stop  
net stop calc.exe  
goto x

```