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A. 5,000 to 10,000
B. 10,000 to 15,000
C. 15,000 to 20,000
D. 20,000 to 25,000
The average adult at rest inhales and exhales something like 7 or 8 liters (about one-fourth of a cubic foot) of air per minute. That totals something like 11,000 liters of air (388 cubic feet) in a day.
The air that is inhaled is about 20-percent oxygen, and the air that is exhaled is about 15-percent oxygen, so about 5-percent of the volume of air is consumed in each breath and converted to carbon dioxide. Therefore, a human being uses about 550 liters of pure oxygen (19 cubic feet) per day.

A. Oxygen
B. Hydrogen
C. Carbon Dioxide
D. Silicon

Oxygen is the most abundant element in the earth’s crust and silicon is next.

A. Oxygen
B. Hydrogen
C. Carbon Dioxide
D. Silicon
Hydrogen is the most abundant element in the Universe; helium is second. However, after this, the rank of abundance does not continue to correspond to the atomic number; oxygen has abundance rank 3, but atomic number 8.

A. 4
B. 5
C. 6
D. 7

A. Star
B. Planet
C. Asteroid
D. Meteor

A device which converts chemical energy into electrical energy is called __________?

A. motor
B. generator
C. moving-coil meter
D. battery

Batteries are devices that convert stored chemical energy into useful electrical energy. It consists of a number of voltaic cells connected in series by a conductive electrolyte containing anions and cations. A battery may be thought of as a clever variant of a standard exothermic chemical reactor that yields chemical products with lower energy content than the chemical reactants.
Also read about A device that converts mechanical energy into electric energy is called_______?

A. Kelvin
B. Thomson
C. Rutherford
D. Bacquerel

A. 1 g/cm3
B. 1.5 g/cm3
C. 2 g/cm3
D. none of these

A. 60
B. 120
C. 180
D. 240

A. also decrease
B. increase
C. remains constant
D. none of these