Answer
a. $140$ yards, $1200\ yard^2$
b. $140$ yards, $1000\ yard^2$
Work Step by Step
a. Given $l=40$ yards and $w=30$ yards, we have the perimeter $p=2(l+w)=2(40+30)=140$ yards, and the area $A=lw=40\times30=1200\ yard^2$
b. Given $l=50$ yards and $w=20$ yards, we have the perimeter $p=2(l+w)=2(50+20)=140$ yards, and the area $A=lw=50\times20=1000\ yard^2$
