$ top -bn1 | awk '/firefox/{print $9,$10}'
9.7 24.1
$ top -bn1p $(pidof firefox)
top - 15:30:49 up 6 days, 14:43, 3 users, load average: 0.16, 0.15, 0.14
Tasks: 1 total, 0 running, 1 sleeping, 0 stopped, 0 zombie
Cpu(s): 10.9%us, 2.5%sy, 0.1%ni, 83.9%id, 1.7%wa, 0.6%hi, 0.3%si, 0.0%st
Mem: 1783188k total, 1526272k used, 256916k free, 27052k buffers
Swap: 3571708k total, 734112k used, 2837596k free, 488564k cached
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
17180 arcfi 20 0 1374m 418m 26m S 27.9 24.0 141:00.28 firefox