Describe the climate throughout the paleozoic, mesozoic, and cenozoic eras.

describe two pieces of evidence for scientists' ideas about the age of earth.

geologic time periods are divided into segments based on two pieces of information. describe them.

the upper rocks in the muav limestone are 505 million years old. the lower rocks in the redwall limestone are 340 million years old. what could explain the gap?

The climate of the Paleozoic Era varied as the period began with large glaciers covering the surface of the Earth, which gave way to warmer temperatures, glacial melt and volcanic activity.During the Mesozoic, the Earth was very different than it is now. The climate was warmer, the seasons were very mild, the sea level was higher, and there was no polar ice.The global climate of the early portion of the Cenozoic Period was much warmer than it is today, and the overall climate of the Earth was much more consistent regardless of proximity to the equator.

Generally speaking, scientists have developed multiple different methods of determining the age of the earth. Two examples are carbon dating rocks and hydrogen dating rocks.

The first stated that sedimentary rocks are laid down in a horizontal manner, and the second stated that younger rock units were deposited on top of older rock units.

The earth's climate prevented the formation of new limestones during that gap of time

Answer: abeexplanation:

1. the question asks the most appropriate, which seems to rule out "all of the above." your choice appears to be the correct one.

2. the protocol described is good for identifying correlation, but not cause and effect. for cause/effect, you need to devise a protocol that will assign the treatment (or not) to groups that have essentially the same "demographics" with respect to all the other variables. your choice regarding control group seems appropriate. random assignment of treatment (choice d) may be appropriate also. (i think you can argue that b and d are just different descriptions of the same method.)

3. d will randomize the birds, but may not guarantee there are 10 in each group. e will do both, so seems the better choice.

comment on question 2

based on the problem statement, it seems clear that confident, attentive drivers are more likely to use daytime running lights. so, the protocol might need to be devised in such a way that the lights would be turned on or off without the driver's knowledge. (an attentive driver will figure it out.) assigning a confident, attentive driver to a group required to drive without running lights might mess with his/her confidence and attentiveness. you don't want your experiment to do that. (nor do you want the experiment to subject a driver to greater risk of accident as a consequence of driving without running lights.) experiments involving human safety are always problematic.

Neither model is able to show the reactivity of potassium.