Student a weighs 75 pounds, and student b weighs 50 pounds. student a gives student b a push while standing on a skateboard as shown in the diagram. after the push, student a moves backward while student b remains motionless. which statement is true?

Which of the following claims does the author support the least

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?

If garbage is left on the street flies in microbes can arise from nothing to feed on it true or false