Determining whether or not an analogy is useful is ____________

While its recreational use is prohibited, GHB is approved for medical use in its sodium salt form, sold under the trade name Xyrem. What condition does Xyrem treat?

a. chronic pain b. cachexia c. cataplexy d. cough e. catatonia

Which woman is at the greatest risk of bearing a baby with Down syndrome?

A) Gemma, age 15 B) Melina, age 24 C) Ursula, age 28 D) Kay, age 44