Which rule is it? Help my dad wants me to get this done tonight and I'm not doing so good with that.. Please provide an explanation too because I'm super confused.

The variable z is directly proportional to x, and inversely proportional to y. when x is 4 and y is 13, z has the value 1.2307692307692. what is the value of z when x= 9, and y= 20

Find the number of positive three-digit even integers whose digits are among 9, 8, 7,5, 3, and 1.

Complete each statement from the information given and the triangle criterion you used. if the triangles cannot be shown to be congruent, leave the box for the second triangle blank and choose for reason “cannot be determined.” carbon - regular hexagon. ∆can ≅ ∆ by