Why aluminum in 1820 had more value than gold​

The number of neutrons is equal to the atomic number minus the atomic mass. a. true b. false

Mary is conducting an experiment on how pollution affects plant growth. how can she ensure that her data are reliable?

While in europe, if you drive 125 km per day, how much money would you spend on gas in one week if gas costs 1.10 euros per liter and your car’s gas mileage is 32.0 mi/gal? assume that 1 euro=1.26 dollars