Which elements are most likely to undergo the same kinds of reactions, those in a group or those in a period?

Apopulation of black bears depends on salmon from a stream for food. if a drought causes the stream to run dry one year, how will this likely impact the black bear population?

Which kind of worm has a closed circulatory system? a planarian b fluke c pinworm d an earthworm

The spermists believed that: the male made the only hereditary contribution to the offspring the male and female traits were blended in the offspring the female made the only hereditary contribution to the offspring the male and the female made equal contributions to the next generation