How many degrees of hardness are defined

on the Mohs hardness scale?
a) 3
b) 7
c) 10
d) 12


c

Physics & Space Science

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The absolute temperature of an ideal gas is directly proportional to which of the following?

A. speed B. momentum C. kinetic energy D. mass

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Which of the following is true about the seasons on Uranus?

A) The seasons on Uranus are not unlike those on Earth or Mars. B) The Uranian rotation axis produces some extreme seasonal effects. C) Like Jupiter, Uranus has little tilt, with its equator always facing the Sun. D) From the Uranian equator, the Sun would remain stationary all the time. E) Uranus' weather will become less turbulent as equinox approaches in 2049.

Physics & Space Science

A proton moving along the x axis has an initial velocity of 4.0 × 10^6 m/s and a constant acceleration of 6.0 × 10^12 m/s2 . What is the velocity of the proton after it has traveled a distance of 80 cm?

a. 5.1 × 10^6 m/s b. 6.3 × 10^6 m/s c. 4.8 × 10^6 m/s d. 3.9 × 10^6 m/s e. 2.9 × 10^6 m/s

Physics & Space Science

How is most of the energy required for secondary wastewater treatment consumed?

A) as electricity to power air pumps for aeration B) as electricity to illuminate UV lamps C) as heat to run distillation equipment D) as electricity to power hydraulic pumps for reverse osmosis E) none of the above

Physics & Space Science