According to the research of Siegel, heroin users are more likely to die from an overdose when they
A) take heroin in an environment in which they have frequently taken it before.
B) take heroin subcutaneously.
C) take heroin in an environment in which they have never taken it before.
D) take heroin in an environment in which they have often taken other drugs before.
E) buy their heroin from a conspecific.
Question 2
A problem faced by theories of drug conditioning is predicting
A) the direction of conditioned effects.
B) whether or not there is a conditional stimulus.
C) whether or not there is an unconditional stimulus.
D) whether conditioned or contingent tolerance will develop.
E) who will become addicted.