30. Bio-Indicators of aquatic health are best observed under which conditions? A. once every ten years
B. at the surface, every year
C. once a year at many depths of water.
D. many times a year at many depths

Adeuteron, 21h, is the nucleus of a hydrogen isotope and consists of one proton and one neutron. the plasma of deuterons in a nuclear fusion reactor must be heated to about 3.02×108 k . what is the rms speed of the deuterons? express your answer using two significant figures.