Answer: The answer is B I'm pretty sure
A) You want to find t such that
.. C(t) = d
.. d = 20 +60*0.95^t
.. (d -20)/60 = 0.95^t
.. log((d -20)/60) = t*log(0.95)
.. t = log((d -20)/60)/log(0.95) . . . . . . time to cool to d degrees (d > 20)
b) C'(t) = 60*0.95^t*ln(0.95)
.. C'(1) = 60*0.95*ln(0.95) ≈ -2.924 °C/min
It’s B okay so first you’ll take 47-20 and that will give you 20 then you’ll divide by 4.50 and then your finally answer will be 6.
Option D:
is the solution
Explanation:
The given expression is 
We need to determine the solution of the expression.
<u>Solution:</u>
The solution of the expression can be determined by solving the expression for the variable x.
Thus, we have,

Adding both sides of the expression by 1, we get,

Dividing both sides of the expression by 3, we get,

Thus, the solution of the expression is 
Hence, Option D is the correct answer.