Answer:
87.3
The answer to get 87.3 is to see if the number in the hundredths place (this case 1) is bigger or the same as the value of 5. If it is round the tenth up but if not then cut the rest of the numbers off.
5.68x10^11
100=10^2
1 billion=10^9
10^2*10^9=10^11
Well really it would have to depend on the flashlight. Is it an led bulb or a regular bulb?