I got some more chemistry

Which of the following is true about the speed of light? it depends on the wavelength.

Asample of sea water contains 6.28g of sodium chloride per litre of solution. how many milligrams of sodium chloride would be contained in 15.0ml of this solution?

Where are the noble gases located in the periodic table? a. in the center b. on the left side c. in the upper right corner d. on the far right side