primary operations (+ * / -) parallel or serial?

Hi

I am a newbie in fortran programming. I have a piece of code which is mainly constructed from elementary operations very similar to :

DO

c=a+b+d+e

f=(a*b )*e

enddo

As I compile and run it in Intel visual fortran, are these operations automatically executed in parallel on both cpu cores I have (intel core(TM) 2Duo T9600)? 

when I check cpu performance from task manager, it shows 50% cpu usage? what should I do to use both cpu cores for such operations?

thanks in advance