Why isn't earth a closed system? a. earth reflects and radiates energy. b. matter continually cycles between the "spheres." c. large amounts of matter currently reach earth from space. d. earthquakes, volcanoes, and hot springs release energy from earth's interior.

Acceleration is a direct result of a.) balanced forces b.) unbalanced forces c.) gravity d.) velocity

The leopard frog and the pickerel frog are two closely related species. in areas where their ranges overlap, the frogs will remain separate species if they

Many farmers prefer cattle without horns because it is safer for their herds. the allele for no horns (n) is dominant to the allele for the presence of horns (n). a farmer mates a male with horns to a heterozygous female without horns. what is the chance that the offspring will have horns?