Why does white water rafting damage river and streams? a) the raft decreases the current within the system. b) the presence of humans decrease the available oxygen in the ecosystem. c) riverbeds are dredged to eliminate hazards. d) the presence of humans scare off aquatic life. e) photosynthetic rate is decreased.

Ayoung boy has been found and police are trying to locate his family they take a dna sample from him and begin collec dna samples from families who have missing children if police use dna samples only from the fathers, which type of dn technology can they use to identify the boy's parent? y-chromosome analysis omtdna (mitochondrial dna) analysis vntrs (variable tandem repeats) o pcr (polymerase chain reaction) analysis