Cold air falls because a. its's icy
b. it's more dense than warm air
c. it's heavier than warm air
d. It's less dense tha warm air

Explain the importance of producers, primary consumers, secondary consumers. and decomposers in an ecosystem

How does pregnancy begin? a) a placenta forms in the uterus b) a sperm reaches an egg in the fallopian tubec) the blastocyst differentiates into two cell types d) contractions begin in the uterine wallapex

If an organ has six haploid chromosomes,how many chromosomes are present. 6 12