How are gold medal cells and human cells alike and different

What is the number of moles of chemical units represented by 9.03x10^24? and how do i show work? (dumb it down )

Iron (3) oxide will decompose in the presence of hydrogen gas and heater to produced iron and digydrogen monoxide white a balanced chemical equation

If 15 drops of ethanol from a medical dropper weight 0.60g, how many drops does it takes from a dropper to dispense 1.0ml of ethanol? the density of ethanol is 0.80g/ml