Select all correct answers choices , which one are they ? 1,2,3,4,5,6 , you can pick more than 1 , me

Ametalworker has a metal alloy that is 30? % copper and another alloy that is 55? % copper. how many kilograms of each alloy should the metalworker combine to create 90 kg of a 50? % copper? alloy?

Given that abcd is a rhombus, what is the value of x?

Dange measures and finds that she can do a vertical jump that is 27.5% of her height if dange is 48 inches tall how high can she jump