In the first three paragraphs, what is the tone of the text? what words or phrases clue you into the tone?

imagine the moment when a great blue whale, undernourished and exhausted from migrating, grunts out its last breath somewhere in the pacific ocean.

then, as the pressure of the surrounding water squeezes the last air reserves from the whale’s lungs, this massive creature begins to sink.

it plunges 700 feet (200 meters) through the ocean’s top layer, the warm “sunlight zone” where algae kick-start life’s food chain with photosynthesis. it drops another 2,600 feet (800 meters) through the cold twilight zone, where no plants live and fish have extra-large eyes to catch the faintest glimmers of sun. it descends down, down, down through 3,300 feet (1 kilometer) or more of the midnight zone. here, temperatures hover close to freezing; deep-sea creatures must flash their own lights to break the darkness; and the weight of the water feels like about 500 bowling balls pressing in on every square inch of the whale’s carcass.