When radioactive thorium (Th) decays it emits a beta particle and produces protactinium (Pa) as seen in the nuclear equation. The atomic mass of thorium missing in the nuclear equation must be A) 233. B) 234. C) 235. D) 238.

What effect would average population growth have on land usage? a. urban use of land would rise to more than 30 percent of available land. b. industrial use of land would rise to more than 30 percent of available land. c. the percentage of available land used as cropland would stay the same. d. cropland would fall to about 10 percent of available land.