Need help with number 7

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

Which number completes the inequality? 2/3 < _ < 7/9

Adeposit of 5500 at 6% for 3 years equals