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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

1.what is where an object is located 2. what is how fast an objects speed is changing 3. what is how fast an object is moving

Select for each of the following statements whether it is correct or incorrect. (a) in an isothermal expansion of an ideal gas. (b) the temperature remains constant. (b) the pressure remains constant. (c) there is work done by the gas. (d) there is heat added to the gas. (e) the change in internal energy equals zero.