"suppose that factories in chicago, illinois, and gary, indiana, produce pollution that affects people living in western michigan. even though the polluting plants and affected individuals can be identified, the externality cannot be resolved privately because of the large number of polluters and affected individuals. this is an example of what type of problem? "

I believe the answer is: transaction costs and negotiating problems.

Transaction cost refers to additional expenses that incurred when we buy or sell a certain goods or services, this could includes things such as unexpected transportation charge, environmental damage, or intermediary charges. Negotiating problems refers to a conflict that might arise between the sellers and the buyers before both of them agree on the term of transaction.

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.

on the first day of new student week, amber revealed to her roommate that she is a lesbian. this is an example of self-disclosure.