SOMEONE PLEASE HELP?

Prove the segments joining the midpoint of consecutive sides of an isosceles trapezoid form a rhombus.
Find the slope of EF and GD.

Given: △abc, ab=15, bd=9 ad ⊥ bc , m∠c=30°. find: the perimeter of the triangle.

The ratio pv to nrt is plotted against pressure for ch4 at 0°c and 200°c. why does the curve for 0°c drop below the horizontal line for an ideal gas whereas the curve for 200°c does not?

In two or more complete sentences describe how to determine the appropriate model for the set of data, (1,1), (3,2), (6,3), (11,4).