what code would allow me to see the average value of ftmpop among countries with a low level of political freedoms?

the dataset is terrorism and ftmpop is Number of fatalities from terrorist incidents in the country, 1998-2004, per million population (U.S. State Department) and lackpfhigh will show = 1 if the country has limited political freedoms and 0 if the country does not have limited political freedoms

would it be: mean(ftmpop, lackpfhigh)

Using R