Suppose researchers marked 400 rabbits and later were able to trap a total of 150 individuals in that population, of which 75 were marked. What is the estimate for total population size

This is geometry. could anyone ? i can't fail this class. my grade is quite low already.

You and a friend race across a field to a fence and back. your friend has a 50-meter head start. the equations shown represent you and your friend's distances dd (in meters) from the fence tt seconds after the race begins. find the time at which you catch up to your friend. you: d=∣−5t+100∣d=∣−5t+100∣ your friend: d=∣−313t+50∣∣

Answer these questions showing your work plz