If Formula Error

If Formula Error

I have a custom field with Characters,
Field Name = Vehicle
Possible Values: CAR, VAN, and etc (drop down)
 
I want to achive following,
 
If selected value is CAR, then multiply the amount by 10, otherwise do nothing.
 
Formula return type is set to "Number"
 
Formula I'm using:
If(${Potentials.Vehicle}==CAR,${Potentials.Amount}*10,0)
I get error
Incorrect Data type of argument
 
If I use following formula
If((${Potentials.Vehicle}=='GSA',${Potentials.Amount}*.0075,0))
I get error
Error: Missing Quote
 
Please help.
 
Thanks in Advance.