A metal drum has a mass of 200kg when empty and 1000kg when filled with 10 meter cubic .what is density?​

What is the frequency of a light wave with a wavelength of 620nm

Lymphocytes known as blastocysts make antibodies that fight infection. select the best answer from the choices provided t f

Sodium chloride, nacl, is formed when a sodium atom transfers its electron to a chlorine atom. the difference in charge between the two atoms creates a(n) attraction that bonds them together.