Answer:
Option A, Ohio River and the Missouri River
Explanation:
The historical evidences clearly indicate that Ohio River did not exist before the last ice advances. Before Ohio and Missouri river, the major glacier drainage of the east-west direction happens in Teays River. When ice of the glaciers blocked the Teaya river valley, then the Ohio was formed.
Like Ohio, Missouri river did also not exist before Pleistocene and during that time the largest drainage in North America take place in the Hudson's Bay
Hence, option A is correct
As a rule of thumb, in order to improve the reliability and accuracy of an experiment, it is best if the experiment is repeated several times. The increased number of trials ensures that the readings observed have minimal random error.
A molted external skeleton.
The geologist time scale was formed when scientists studied rock layers and index fossils worldwide. With this information, they placed Earth's rocks in order by relative age. Later, radioactive dating helped determine the exact age of the divisons in the geologic time scale.
This scale is organized by the 4.6 billion years of earth's history into sections based on important changes seen in the geologic record. The largest intervals are called eons, with each eon containing many millions of years.
In precambarian time the processes that affect Earth's surface have lessened the erosion on the surface. Earth was being hit by meteorites every second. Now there is water erosion and there wasn't back then. The surface changes have lessened over time.
Answer:
cytoskeleton is a structure that helps cells maintain their shape and internal organization, and it also provides mechanical support that enables cells to carry out essential functions like division and movement
