Why can rats smell almost three times more compounds than humans?

Why is excretion necessary to maintain homeostasis?

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

Awave has a wavelength of 15 mm and a frequency of 6 hertz. what is its speed?