Question 2 (2 points) Which of the following best explains why matter must travel through cycles?
a
There is an unlimited amount of matter in the universe, so it can take on any form at
any time.
b
There is a fixed amount of matter in the universe, so it must take on different forms
at different times.

Ais the

Homologous chromosomes with heterozygous alleles d) heterozygous chromosomes with homozygous alleles

Mars and earth have quite a few things in common. both are  terrestrial planets, both are located within the sun’s  habitable zone, both have  polar ice caps, similarly  tilted axes, and similar  variations in temperature. and according to some of the latest scientific data obtained by rovers and atmospheric probes, it is now known that mars once had a  dense atmosphere  and was covered with  warm, flowing water.

What i dont get the  questions