Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Carbon dioxide is an example of a material that easily undergoes sublimation.
Carbon dioxide is an example of a material that easily undergoes what?

Municipal type of pollution comes from sewage, storm drains, septic tanks, boats, and runoff from yards.
What type of pollution comes from sewage, storm drains, septic tanks, boats, and runoff from yards?

Because atoms have equal numbers of positive protons and negative electrons, they possess a neutral charge.
Because atoms have equal numbers of positive protons and negative electrons, what kind of electric charge do they possess?