Doctors use the radioactive isotope chromium-51 to label red blood cells in the human body. Chromium-51 gives off relatively alpha particles that can be stopped by . A) energetic; lead
B) weak; a sheet of paper.
C) weak; a thin sheet of copper.
D) energetic; a thick sheet of copper.

Arafura file snakes are large, aquatic, non-venomous snakes found in the flood-plains of australian rivers. they feed only on fish found in the rivers. it has been observed that heavy rainfall in the wet season in one year leads to prolonged inundation of the floodplains lasting a year or longer. it has also been observed that these snakes remain in good physical condition after a flood. explain how the file snake population in a region is likely to be affected by the prolonged inundation of a flood-plain.

Amale bird-of-paradise uses a dance to attract mates in which it flaps its tail feathers on the ground and jumps around a potential female mate. a different male bird-of-paradise does a similar dance but it jumps around the female in the opposite direction. the female bird is only attracted to one style of dance, in one direction. this is an example of speciation.

Lactic acid and energy are produced in muscle cells during choose 1 aerobic respiration cellular respiration anaerobic respiration cellular division