What is the most likely cause of teenage pregnancy?

Astructural difference between the trachea and esophagus that prevents the trachea from collapsing is the presence of: a) smooth muscle b) skeletal muscle c) respiratory cilia d) rings of cartilage

If your emotional energy is low, your attitude will likely a. be more negative. b. not be impacted. c. vary substantially. d. be more positive.

Mason joined the water polo team at his school. as part of his conditioning, mason's coach requires a 25-minute run during practice. mason's heart rate reaches 125 beats per minute, but his target heart rate zone is 138—183 beats per minute. what should mason do to get the most benefit for his heart? increase the amount of time he runs increase the speed at which he runs decrease the amount of time he runs decrease the speed at which he runs