Answer:
The Great Plains are a vast high plateau of semiarid grassland. Their altitude at the base of the Rockies in the United States is between 5,000 and 6,000 feet (1,500 and 1,800 metres) above sea level; this decreases to 1,500 feet at their eastern boundary.
BRAINLIEST PLEASE?
Color and luster are two ways to identify an unknown metal. Other ways include weight and composition.
Backfilling is the right one
Answer: 3.6 seconds
Explanation: Geologic time is a way of measuring time based on events in the history of the Earth. If we compress this into one year, a single geologic year equals 4.6 billion years because the planet was formed 4.6 billion years ago.
Columbus arrived in the New World in August 1492, 528 years ago.
If 4.6 billion years = 1 year in geologic time,
528 years = 528 X 
=3.6 seconds
<em>(I broke the year down into seconds by breaking it down into days, then hours, minutes and seconds because the value is very small)</em>
<em />
<em>So, if we compress geologic time into a single year, only 3.6 seconds have elapsed since Columbus arrived in the New World</em>
<em />
I just did this lesson, and the answer is B.
I hope this helps you!
-Mikayla