Plz me get the answer to these asap

Factor completely. 4p^2 + 36p + 81 express the answer in the form (ap + b)^2

In chemistry,n molecules of an ideal gas have pressure, volume, and tempersture that stand inthe following relation, where r is constant. solve the equation for n,the number of molecules. pv=nrt

Convert to the greater unit before finding the perimeters of this rectangle: 6ft. 6in. by 7ft.