What important milestone happens with the fetus during the second trimester? a. it makes sucking motions
b. it moves lower in the mother's pelvis
c. it turns head down
d. it can open and close its eyes

Which of the following does not describe a physical property of iron? a iron is silvery-white or gray in color. b iron has a boiling point of about 3,000°c. c iron is a magnetic element . d iron and sulfur react to form iron sulfide.

Which gas found in the earth's atmosphere greatly impacts the daily range of temperature on earth. a) oxygen b) hydrogen c) nitrogen d) water vapor

Which of the following is true of metabolism in its entirety in all organisms? a) metabolism depends on a constant supply of energy from food. b) metabolism uses all of an organism's resources. c) metabolism consists of all the energy transformation reactions in an organism. d) metabolism manages the increase of entropy in an organism.