Premise:
"Other nation products--its purported AIDS cure, for instance--have undermined their claim that black businesses are less exploitative than white ones."
Hypothesis: There are no products which could undermine the claim that business is less or more exploitative than any other.

no

Premise:
"1 The information obtained from these reports becomes part of the publically available data base known as the Toxic Release Inventory or TRI."
Hypothesis: The information will be very useful in the near future.

it is not possible to tell

Premise:
"And Johnny joined Howard when they raised that Confederate troop here."
Hypothesis: Johnny and Howard don't know each other.
no