It's b the number multiplied by 10 must be less than 10
Answer:

at least means it need to be more or the lowest it can be is 18
133 x 99 = 13167
100% correct
Log(ab) = log(a) +log(b) . . . . . . . . . this is the whole point of logarithms
The correct answer you're looking for would be the third option. C.) It is the net in the bottom left corner.
I hope this helps!! If you have any questions don't hesitate to ask!! :)