Why is copper(ii) oxide "cuo" instead of "cu2o"

Which is a character of nuclear fusion but not nuclear fission

If a || b and e || f, what is the value of y ?

Great amounts of electromagnetic energy from our sun and other bodies in space travel through space. which is a logical conclusion about these electromagnetic waves? their energy must be very their frequency must be very low these waves can travel without a medium they only travel through a vacuum of space