Question 329469
D1={{{40}}} cm
D2={{{40(0.9)=36}}} cm
D3={{{36(0.9)=40(0.9)^2=32.4}}} cm
D4={{{32.4(0.9)=40(0.9)^3=29.16}}} cm
D5={{{29.16(0.9)=40(0.9)^4=26.244}}} cm