I need help with these 4

If sr is 4.5cm and tr is 3cm, what is the measure in degrees of angle s?

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

Put the equation in slope intercept form by solving for y