Help with science Anayliss Questions ASAP

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Density of salty water as compared to the density of pure water is(a) is less(b) is always equal(c) is always more(d) may be less or more

In 1980, alfa romeo introduced the first system to smooth a rough idle caused by ignition and camshaft timing changes.

Which is not a characteristic of a heat pump? a. it is used in air conditioners. b. it uses a refrigerant. c. it requires no work. d. it reverses the normal flow of thermal energy.