To identify which specific brain areas are most active during a particular mental task, researchers would be most likely to make use of a(n):

pet scan

hemispherectomy

ct scan

lobotomy

brain lesions

Some connecting rods have to lubricate the cylinder wall or piston pin. the answer is letter d. graphite coating can be a major  additive to many  coating  systems and things such as connecting rods.  it functions as a refractory, lubricant, thermal conductor, and electrical conductor for a machine or thing to enhance its work.