When air contains as much air as it can at a certain temperature the air is

the "dirty dozen" chemicals banned in an international treaty are formally known as persistent organic pollutants, or pops. the united nations environment program provided this background on what they are and what they can do to humans and wildlife.

i hope this

b tumor cells have a cell wall instead of a membrane

explanation:

tumor cells different from normal cells because tumor cells have a cell wall instead of a membrane.

yes, because even though a theory has a  lot of evidence to support it, it is not always true