Or search by topic
It is important to be aware throughout that these questions are (deliberately!) not as 'precisely' stated as typical textbook questions. For example, the phrase 'If she had continued running ...' from lane 2 requires an assumption to be made before computation of an answer.
There is no absolutely 'right' way to make these assumptions, although assumptions need to be made clearly.
One possible assumption might be that a runner runs at their average speed for the full distance.
Can you prove that the sum of the distances of any point inside a square from its sides is always equal (half the perimeter)? Can you prove it to be true for a rectangle or a hexagon?
The Earth is further from the Sun than Venus, but how much further? Twice as far? Ten times?