premise: 3 It should be noted that the toxicity ( LC50 ) of a sample observed in a range-finding test may be significantly different from the toxicity observed in the follow-up chronic definitive test ( 1 ) the definitive test is longer ; and ( 2 ) the test may be performed with a sample collected at a different time , and possibly differing significantly in the level of toxicity .
hypothesis: The toxicity of a sample in the ragne-finding test might be very different from the toxicity in the follow-up test .