Charles has experienced persistent problems with voluntary control over ejaculation upon penetration. Charles most likely has:

Reed has undergone profound behavior changes recently. He has been aggressive and violent, eats very little, and has acted paranoid. These marked changes in his behavior are probably the result of ________ abuse

a. amphetamine b. barbiturate c. alcohol d. LSD

Tahir, an Arab, and Jan, a Swede, meet at a dinner for international students. Because the cultures of the two men differ with regard to ________, both may feel uncomfortable during their conversation

a. knowledge of a common eating etiquette b. attitudes toward higher education c. explicit laws d. conversational distance