Toxic waste spills are a direct source of water pollution.
a. true
b. false

During the winter, this species of fox has white fur, but in the summer, it has brown fur. what environmental change may have lead to this fox's fur color? snow cover increase in sun's brightness volcanic eruption global warming

The images show two species of tree frogs in a particular region. the gray tree frogs are adapted to the trees of the woodlands, while the green tree frogs can survive in woodlands or grasslands. the gray frog was abundant in the woodlands. because of climatic changes, most of the trees in the region died, and the woodlands changed to grasslands. in such a case, the . the gray tree frog is closely related to the green tree frog genetically, but they have different mating calls. this suggests that speciation occurred because of .

Skulls of homo sapiens were found during an excavation. the skulls were preserved because the bodies were frozen. so, these fossils are ( 1 ) fossils. ( 1 ) a. mineralized b. mold c. original-tissue