I interviewed at Bi-Mart (Madras, OR) in September 2016. The interview lasted about 25 min and was extremely laid back. He spent more time talking about Bi-marts operations and friendly, for the employee, work place then anything else.
Confidence votes 13. Whales, like otters, porpoises, and all other swimming mammals, undulate their spines rhythmically, waving their tails and flipping the flukes at the end, propelling them forward.
A whale's tail has two lobes or flukes, made of dense collagenous material; the flukes are horizontal because whales evolved from land animals who walked on four limbs. The spines of animals who walk on 4 legs are flexible in an up and down motion, this is how the animal locomotes, by flexing the spine.