Which metallic crystal structure has a coordination number of 8

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

Can someone me with 3 and 4 plz. this is for masteries test.

Water is initially present in a state where its molecules are far apart. during a change of state, its molecules slow down. which change of state has most likely taken place? from a gas to a liquid from a liquid to a gas from a solid to a liquid from a gas to a plasma