You may have $26 I not a genius but this is easy
For this case we have an equation of the form:
y = A * (b) ^ t
Where,
A: initial amount
b: decrease rate
t: time in years.
Substituting values we have:
7 = A * (0.5) ^ ((1/20) * t)
For t = 45 years we have:
7 = A * (0.5) ^ ((1/20) * 45)
Clearing A:
A = 7 / ((0.5) ^ ((1/20) * 45))
A = 33.3
Answer:
the density of the substance when it was deposited 45 years ago was:
A = 33.3 milligrams per square centimeter
Answer:
your answer is c hope this helps let me know if im wrong or nah
Step-by-step explanation:
The circumference is the diameter times PI
The exact circumference would be 9PI cm
The approximate circumference would be 9 x 3.14 = 28.26 cm
