If you start with 500.0 g of a radioisotope with a half-life of 3.0 days, how much of the original isotope will still be in the sample after 18 days?

How does the principle of electromagnetism explain the interaction between earth’s magnetic field and the solar wind?

How is the solubility of a carbon dioxide gas in water increase?

What do electromagnetic waves carry? how are they produced through which media can they move? where do they transfer energy? what do they not transfer? what do mechanical waves carry? how are they produced? through which media can they move? where do they transfer energy? what do they not transfer?