A woman who has had five preganacies tests positive for HIV by Western blot. What is the most likely reason for this result

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

Is there any species that went extinct in recent years due to natural causes (not caused by human interaction). if so, what caused it?

About __ of the mass of the cell is water