Throughout centuries, mankind used different methods to measure time. List
the methods below historically from oldest to newest.
To measure time
1. People used back and forth motion (ossilation) of pendulums.
2. People used water dripping at a constant rate.
3. People used ossilation of quartz crytals placed in an electric circuit.
4. People used the shadow of a stick as sun travels across the sky.
5. People used atomic clocks using Cesium atoms.

trig 15.3 cos

c. newton's third law of motion

when jerome paddle in flowing river towards east the net speed of jerome will increase

so the net speed of jerome will be given as

now the speed of paul will be same as it is given as he is running on the ground

so

so here we can say since the speed of jerome is more so he will win the race

now as we know the distance so the time difference is given as

so jerome will reach first and the time difference will be 203.55 s or 3.4 min