4/5 ÷0.6+1 3/5 · 1/6 calculate

Can somebody 1. what is the formula for finding the vertical distance between two points on a coordinate plane?

Rhombus adef is inscribed into a triangle abc so that they share angle a and the vertex e lies on the side bc . what is the length of the side of the rhombus if ab=c, and ac=b.

The experience c-0.25c can be used to find the cost of an item on sale for 25% off which expression beloit equivalent to c-0.25c