Context: Mammals include the largest animals on the planet, the rorquals and other large whales, as well as some of the most intelligent, such as elephants, primates, including humans, and cetaceans. The basic body type is a four-legged land-borne animal, but some mammals are adapted for life at sea, in the air, in trees, or on two legs. The largest group of mammals, the placentals, have a placenta, which enables feeding the fetus during gestation. Mammals range in size from the 30–40 mm (1.2–1.6 in) bumblebee bat to the 33-meter (108 ft) blue whale.

Question: Which specific mammal is the largest today?
Answer: blue whale

Question: Which mammal is the smallest?
Answer: bumblebee bat

Question: Which four legged mammal is considered to be the smartest?
Answer: elephants

Question: About how small is the average bumble bee bat?
Answer: 30–40 mm (1.2–1.6 in)

Question: What do the largest group of mammals, elephants, have that helps the fetus during gestation?
Answer: Unanswerable

Question: How small is the average fetus?
Answer: Unanswerable

Question: What are some fetuses adapted for?
Answer: Unanswerable

Question: What is another name for a large elephant?
Answer: Unanswerable

Question: What does a placenta help bumblebee bats do?
Answer: Unanswerable