Help asap! 20 pooints best answer for both questions

For the equations below which statement is true ?

5/6+7/8what is the answer sealsdbdbshd

A3-dimensional figure has a square base and 4 lateral faces that meet at a point. explain the difference between the cross sections when a slice is made perpendicular to the base through the vertex, and when a slice is made perpendicular to the base and not through the vertex