Approximately 180 million years
All continents were united in one super continent known as Pangaea. according to Wegener, an observation into the shape and designs of the continents reveals that all the continents were once one large mass. the continent begun to split approximately 180,000 million years ago.
Answer:
After the bombing at Pearl Harbor President Roosevelt addressed Congress asking to declare war on Japan.
When we have a 75% of the wound healed, we have the following area:
area of the wound=(100%-75%) (initial area) =25% (initial area)
In this case:
area of the wound=25%(80 cm²)=20 cm²
A(t)=80(10^-0.023t)
If A(t)=20
Then:
20=80(10^-0.023t)
10^-0.023t=20/80
10^-0.023t=0.25
log (10^-0.023t)=log 0.25
-0.023t log 10=log0.25 log 10=1
-0.023t=log0.25
t=log 0.25 /-0.023
t=26.176≈26
The wound be healed (75%) in 26 days
