How much should a regular person sleep?

How could natural selection best be used to explain the evolution of the white fur of arctic fox

Which of the following represents a difference between viruses and viroids? a) viruses infect many types of cells, whereas viroids infect only prokaryotic cells.b) viruses have capsids composed of protein, whereas viroids have no capsids.c) viruses have genomes composed of rna, whereas viroids have genomes composed of dna.d) viruses cannot pass through plasmodesmata, whereas viroids can.

Which short-term goal might prompt someone to seek for mental and emotional challenges? saving for retirement buying a house in 10 years reducing conflict with family owning a company eventually