Nucleotide dna strand

Why is it important to reduce the number of chromosomes in half when forming gametes for sexual reproduction?

If scientists are wrong about earth's age based on radioactive material and the decay rates are really much faster, how would nuclear power plants be affected?

Matthew decided he wanted to hike up mount everest. on his way to the top, it began to snow and the temperature dropped to -10°f. matthew forgot to wear a heavy jacket so his body began to shiver beyond control. in this case, matthew's body shivering is the to a drop in temperature. * 0 points reflex stimuli responce environmental facto