I think by using data collected by Tycho Brahe
Answer:
10250 N/C leftwards
Explanation:
QA = 4 micro Coulomb
QB = - 5 micro Coulomb
AP = 6 m
BP = 2 m
A is origin, B is at 4 m and P is at 6 m .
The electric field due to charge QA at P is EA rightwards

The electric field due to charge QB at P is EB leftwards

The resultant electric field at P due the charges is given by
E = EB - EA
E = 11250 - 1000 = 10250 N/C leftwards
Answer:
When there is wind it takes longer
Explanation:
With no wind, the round trip time is

When we have a constant wind speed w

comparing the reciprocal times;

This means that t1 is smaller than t2, ergo, it takes longer with wind
That would be like dropping your cell phone on to the ground by accident. The object (cell phone)'s gravitational potential energy would be converted to kinetic energy or energy in motion more precisely. This is just a hypothetical example though.
The one that both benefits each other is the one I think it's mutalistic