Suppose you have two lens 100cm and 4cm respectively which should be your eyepiece for a compound microscope ​

asthenosphere and convection

d) physical means can be used to separate the components of air.

the answer is false. this is because for ice to melt, it requires latent heat of melting. latent heat means heat energy required to change phase without any increase in temperatures. therefore, the ice will take energy from the environment to melt hence atmospheric temperatures will reduce.