D would be the most reasonable answer.
Answer:
The heat equation can be written as. ∂ u ∂ t = α ∇ 2 u. where u(x, y, t) is the temperature field that varies in space and time, and α is the thermal diffusivity constant.
New Zealand and the outback
A city that has a problem with smog is most likely a MDC and is experiencing it due to heavy air pollution. <span />
