a) V_s=\(\frac{Π}{4}\)∗d²l
b) V_s=\(\frac{Π}{16}\)∗d²l
c) V_s=\(\frac{Π}{32}\)∗d²l
d) V_s=\(\frac{Π}{4}\)∗d³l

Answer: a
Explanation: V_s=\(\frac{Π}{4}\)∗d²l describes Swept volume or the displacement. Volume is swept when the piston moves between top dead centre and bottom dead centre during the movement of piston.