Elements and compounds with a constant composition can be identified and separated by all but their
a. color.
b. conduction.
c. density.
d. solubility.

To sciences do not agree on which type of grocery bag is better for the environment what is most likely to come out come out of the disagreement

Astudy by solloch and et. al., in 2017, gives the map above which shows the frequency of alleles with a ccr5-delta32 mutations over 87 different countries. this mutation deletes the presence of a co-receptor (ccr5) on the outside of human t-cells (lymphocytes). some viruses, such as the one responsible for the black death and human immunodeficiency virus (hiv), require this receptor for attachment to host cells during the infection process. the black death was an epidemic that passed over northern europe during the 14th century killing nearly 60% of europeans. according to this information, which explanation best explains why northern europeans show a greater immunity for hiv than some other parts of the world?

Three applications for admission to a local university are checked, and it is determined whether each applicant is male or female. the number of sample points in this experiment is