Answer:
The sample would double in 9 hours
Explanation
The number of hours it will take for the sample to double can be found using the 72 rule.
The 72 rule is such that a growth rate would double itself by it is used in dividing the number 72 as shown below:
number of hours =72/8=9 hours
The number of hours it would take the sample to double is 9 hours as computed above.