Bottlenose Dolphins Breathe Air but Can Sleep in the Ocean

question 33

Multiple Choice

Bottlenose dolphins breathe air but can sleep in the ocean because

• A) they cease breathing while sleeping and remain underwater.
• B) they sleep for only 30 minutes at a time, which is the maximum interval they can cease breathing.
• C) they fill their swim bladder with air to keep their blowholes above the surface of the water while they sleep.
• D) they move to shallow water to sleep, so they do not need to swim to keep their blowholes above the surface of the water.
• E) they alternate which half of their brains is asleep and which half is awake.

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Definitions:

Levered Firm

A company that employs debt in its capital structure, as opposed to an unlevered firm which is financed only through equity.

Annual Coupon

The fixed interest payment a bondholder receives from the bond's issuer each year.

Perpetual Debt

Debt instruments with no maturity date, allowing issuers to pay interest indefinitely without repaying the principal.

Coupon Rate

The yearly interest rate paid on a bond, shown as a percentage of its nominal value.