ini maksudnya gimana gak ngerti

Diketahui

D= d

Maka r = 1/2 D

= 1/2 d

t = d

Ditanya Lp....?
Dijawab

Lp = 2 x π x r x ( t + r )

= 2 x π x (1/2)d x ( d + 1/2d )

= π d x ( 3/2 )d

= 3/2 π d^2

Jawaban A