The ends of the geologic eras such as the paleozoic and mesozoic are marked by
a. mass extinctions.
b. index fossils.
c. radioactive decay.
d. climate changes.

Which of the following is the earliest era of earth's geologic time scale? cenozoic mesozoic precambrian paleozoic

The lake of the ozarks is a human-made lake, so it collects runoff from coal strip-mining, fertilizers, resort wastewaters, and septic drainages. the average lake temperature is between 10∘c and 21∘c. consider the physical requirements for growth and multiplication that would allow fecal coliforms to “blossom” in the lake of the ozarks. which of the following would accurately describe these organisms? check all that apply. psychrophiles facultative halophiles extremophiles mesophiles hyperthermophiles

Aremote community desperately needs more electrical energy. it is located in an area with the following characteristics: average wind speed of 15 – 20 km/hr some medium-sized rivers with slow-moving currents few coal deposits some oil exploration being conducted within 400 miles based on the above information, which energy source would be the most economical and safest for the community to pursue? a. fossil fuel b. hydroelectric c. nuclear d. wind