Fema had supplied trailers for people whose homes had been destroy during hurricane katrina and later it became apparent that the air in these trailers was contaminated with unhealthy levels of

Katrina was a major disaster and the contamination with the unhealthy levels of formaldehyde did not help at all.  Formaldehyde is a colorless gas that has a quite strong smell and at a room temperature is not flammable but unfortunately the smell is not the only problem as formaldehyde can cause severe health issues.

giant impact theory - the moon was formed from the collision between earth and another mars-sized body.

colliding planetesimals hypothesis - the moon was formed from the same cloud of material as earth.

capture hypothesis - the moon was locked into orbit by earths gravity as it was passing by it.

accretion hypothesis - the moon was formed from collisions and combining of planetesimals.

i think this is right, if not and you know better let me know.