We have the following:
The force of wind: F = 150 pounds
The square of the winds speed: V = 30 miles per hour
The area of the windows: A = 4*5 = 20 square feet
The formula is:
[tex]F=kAV^2[/tex]replacing:
[tex]\begin{gathered} 150=k\cdot20\cdot30^2 \\ k=\frac{150}{20\cdot900} \\ k=\frac{1}{120} \end{gathered}[/tex]now, the force of wind with 60 miles per hour and 12 (3*4) square feet
[tex]\begin{gathered} F=\frac{1}{120}\cdot12\cdot60^2 \\ F=360_{} \end{gathered}[/tex]The answer is 360 pounds