Which gas makes up 78 percent of our atmosphere but can be used by plants only when transformed by bacteria first?
a. hydrogen
b. oxygen
c. carbon dioxide
d. nitrogen

Matthew decided he wanted to hike up mount everest. on his way to the top, it began to snow and the temperature dropped to -10°f. matthew forgot to wear a heavy jacket so his body began to shiver beyond control. in this case, matthew's body shivering is the to a drop in temperature. * 0 points reflex stimuli responce environmental facto