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
The usual goals of monetary policy are to achieve or maintain full employment, to achieve or maintain a high rate of economic growth, and to stabilize prices and wages. Until the early 20th century, monetary policy was thought by most experts to be of little use in influencing the economy. Inflationary trends after World War II, however, caused governments to adopt measures that reduced inflation by restricting growth in the money supply.
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