To find the value of the penny after 14 days, Mr. Hibbard would use the expression \(0.01 \cdot 2^x\), where \(x\) is the number of days since he found the penny.
Since he wants to find the value after 14 days, he would substitute \(x = 14\) into the expression:
\[ 0.01 \cdot 2^{14} \]
Now, calculating \(2^{14}\):
\[ 2^{14} = 16384 \]
Then, multiply this by \(0.01\):
\[ 0.01 \cdot 16384 = 163.84 \]
This computation shows that the penny is worth $163.84 after 14 days.
The correct response that reflects this calculation is:
Mr. Hibbard substituted \(x=14\) into the expression \(0.01 \cdot 2^{14} = 163.84\).
(Note: The response has a typo showing \(163.48\); it should be \(163.84\) in the explanation.)