An acid is a proton donor
To turn the flow of electricity on or off. Probably wrong
The balloon has traveled 30 meters up from the bicyclist and since it's rising 5 meters per second, 2 seconds later it will travel 10 meters higher. 2 seconds later the bicyclist will travel 20 meters away. so 10+20+30= 60 meters away from each other.
A part of organism that is typically self contained and have a specific vital