Answer
See the answer below.
Work Step by Step
A: $r=l/2$
Square area: $l^2=4r^2$
Area of the quarter circles: $4\times (\pi.r^2)/4=\pi.r^2$
Coverage: $\pi/4\times100\%=78.53\%$
B: $r=l/2$
Equilateral triangle area: $\sqrt3/4.l^2=\sqrt3.r^2$
Area of the 1/6th circles: $3\times (\pi.r^2)/6=\pi/2.r^2$
Coverage: $\pi/2\sqrt3\times100\%=90.69\%$
