An example of diffusion in your everyday life

In the first law of thermodynamics, triangle e=q-w, what does q stand for

Which statement best describes the superposition principle? a.) if two in-phase waves arrive simultaneously at a point, their amplitudes add up b.) if two out-of-phase waves arrive simultaneously at a point, their amplitudes add up c.) if two in-phase waves arrive at a point one after another, their amplitudes add up d.) if two out-of-phase waves arrive at a point one after another, their amplitudes adds up

Does heating a metal wire increase or decrease its electrical resistance? why?