Question

I need a and b answered with b answer in exact answer format.

According to modern​ science, Earth is about 4.5 billion years old and written human history extends back about​ 10,000 years. Suppose the entire history of Earth is represented with a

100​-meter-long

​timeline, with the birth of Earth on one end and today at the other end.a. What distance represents

4

billion​ years?

b. How far from the end of the timeline does written human history​ begin?

a.

4

billion years is represented by

nothing

meters

of the timeline.

​(Type an integer or decimal rounded to the nearest tenth as​ needed.)

Answer 1

Acc to question,

100 meter long line represents 4.5 billion years.

(a) So, 1 year is at a distance of 100/(4.5 billion) meter

So, 4 billion years is at a distance of (4 billion)*(100/(4.5 billion)) meter

= 400/4.5

= 88.9 meters(rounded to nearest tenth)

(b) human history is 10000 years old.

So, it is represented by 10000* (100/ 4.5 billion)= 1000000/4500000000= 1/4500 from the end of timeline

= 0.000222 meters

= 0 meters (rounded to nearest tenth)

Please upvote . Thank you.