How do i solve the following question ( show work):
oxygen has three naturally occurring isotopes in the following proportions: oxygen-16, 99.762% (15.994 91 amu); oxygen-17, 0.038000% (16.999 13 amu); oxygen-18, 0.2% (17.999 16 amu). what is the average atomic mass of oxygen?

The agent of mechanical weathering in which rock is worn away by the grinding action of other rock particles is call

The difference between the atomic number of an element and the element’s atomic mass is the number of ions.

Nebulae are enormous clouds in outer space. they are made mostly of hydrogen gas, helium gas, and dust. some nebulae glow brightly, while others do not. the stars that people see are huge, bright balls of glowing gas. they are made mostly of hydrogen and helium. which statement correctly describes other ways in which nebulae and stars are different? a. stars can form inside a nebula but a nebula can never be produced by any star. b. a star always has a higher density than a nebula. c. stars can never form inside a nebula but a nebula can be produced by any star. d. a nebula always has a higher density than a star.