2. Using the guidelines from this section, rewrite the following passages to use numbers and figures appropriately.

a. Penguin is the common name for fifteen species of flightless marine birds. They live on four continents in the Southern Hemisphere. One penguin, the Galapagos, lives within six degrees of the equator.

Penguins can swim through the water at speeds of up to twenty-five miles per hour. The largest species, the emperor penguin, ranges from three to four feet tall. The smallest, the Adelie, stands about two feet tall.

b. On the twenty-third of February in the year two thousand and seven, one hundred forty-two mallards were tagged off the coast of Florida. For five years, researchers tracked approximately seventy of the mallards over three hundred and ninety-seven miles. The ducks survived in temperatures as low as minus ten degrees Celsius. A report was distributed to twenty-seven agencies in seven states. The research cost six thousand forty-five dollars and fifty-six cents. It is estimated that seven and one half million mallards inhabit the southeastern area of the United States. Biologists estimate that ninety percent of the mallards follow predictable patterns of migration.