Yes they do because they just have to
Initial velocity = 
acceleration in the downward direction = -9.8 
Final velocity at the highest point = 0
Maximum height reached = 0.410 m
Now, Using third equation of motion:




Speed with which the flea jumps = 
Answer:
9654.34 m
Explanation:
from conservation of momentum

And from Conservation of Energy

The lines can be traced out with a compass. The needle is like a permanent magnet and the north indicator is the north end of a magnet.