A student is testing a silver colored rock sample with the lab equipment shown in the diagram above. The silver colored rock completes the circuit and lights the bulb.
The student concludes the sample could be which of the following?
I. metal
II. metalloid
III. nonmetal

Scientist have long study the earths climate by looking at which of the following? the earths orbit. the earths rock layers. the antarctic ice. the earths oceans.

Which of the following factors would not contribute to allopatric speciation? a) a population becomes geographically isolated from the parent population.b) the separated population is small, and genetic drift occurs.c) the isolated population is exposed to different selection pressures than the ancestral population.d) different mutations begin to distinguish the gene pools of the separated populations.e) gene flow between the two populations is extensive.

Up to what percentage of the world's flora consisted of cycads during the triassic period? 100% 75% 50% 20%