Well, I'm not going to give you the answers, but first erase the "(variable) =". They already gave you the value of the variables, so you just have to multiply the variables, like for example, "7/8 × c, c = 6". It's telling you to multiply 7/8 by 6. The rest goes for everything and in the future, instead of writing it as 7/8 × c, it'll say 7/8c.
So yeah, just multiply the number by the variable, which already has a given value.
