What structure is also known as the pacemaker of the heart?

If one of your friends tries to get you to stay out later than your curfew, you should: a. go along with it because your parents are too strict anyway. b. yell at them about what a stupid idea it is. c. say you don't want to, but if they insist, you stay. d. tell them that you're going home, but they can stay out if they want to.

Synovial fluid serves as a lubricant to prevent friction between two parts that move on each other such as in the case of and bones.

What exercise allows you to specify the muscles to be traineda. i sonicb. anaerobicc. isometricd. aerobic