Answer:
The required smallest power of 10 that would exceed 999,999,999,991 is 12.
Step-by-step explanation:
Given : Number 999,999,999,991.
To find : What's is the smallest power of 10 that would exceed number ?
Solution :
Let the required power be 'x'.
According to question,

Taking log both side,

Apply logarithmic property, 


Using calculator,

Therefore, The required smallest power of 10 that would exceed 999,999,999,991 is 12.