Consider the following properties. i) the temperature (in ◦c) at which ice melts ii) the color (green) of nickel chloride iii) the energy (in kj) produced when gasoline burns iv) the cost (in $/gal) of gasoline v) the price (in $/g) of platinum vi) the humidity (in %) of the atmosphere vii) the air pressure (in psi) in a tire viii) the hardness of concrete