Whales have what seem like remnants of a pelvis and femur, as shown here.

An x-ray image of a whale tail. The pelvis and femur bones are shown.

What are these structures an example of?
transitional structures
analogous structures
vestigial structures
adapted structures

answer; /// the correct )

b. read the phase at the intersection of any given temperature and pressure.

its temperature is increasing. this causes molecular vibrations to increase.

not necessarily. higher fitness requires the organism to be reproductive successful. for example, an organism at age 10 with 15 offspring is much more fit than an organism at age 15 with only 5 offspring.