Final answer:
The lethal dose of caffeine for a hamster like Elmo Q. Hamster is significantly lower than for humans, and caffeine can be extremely harmful to hamsters.
Step-by-step explanation:
The question of how many cups of coffee would be lethal to Elmo Q. Hamster, who weighs 162.5g, involves understanding the biology of small mammals and the effects of caffeine. While the exact lethal dose can vary, for humans, the lethal dose (LD50) of caffeine is estimated to be about 150 to 200 milligrams per kilogram of body weight. Hamsters are much more sensitive to caffeine, and the lethal dose for them would be significantly lower. It's imperative to note that feeding a hamster coffee or any other caffeine-containing substance can be extremely harmful and should never be done.