I NEED HELP ASAP!! The smallest land area required to house our earth's population is approximately the size of what nation?

The distance a car travels between the time the driver decides to stop the car and the time the driver puts on brakes is called the reaction distance. how does the reaction distance change with speed? a.reaction distance decreases with with speed b.reaction distance stays the same with speed c.reaction distance increases with speed. d.there is not enough information to answer the question