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Challenge #17

Question 1.
What is the name, derived from the Latin word for 'warmth', given to the units of the energy content of foods ?
Question 2.
The pH of a solution is a measure of its concentration of hydrogen ions. A neutral solution has a pH of 7.0. What type of solution has a pH of greater than 7.0 ?
What is the linear measurement whose name is derived from a latin word meaning 'measuring rod' and that has been defined as being: one ten-millionth of the Earth's quadrant; 1,650,763.73 wavelengths of the orange-red light emitted by the radiocative isotope krypton-86; or, as the distance that light travels in a vacuum in 0.0000003 of a second?

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