Nomor 6 dan 16 tolong bantuu please

Cermin CEKUNG
h = 5 cm
s = 20 cm [ruang II]
f = 15 cm
h' = ___?

h' = h [f / (s – f)]
h' = 5 [15 / (20 – 15)]
h' = 15 cm ←
Tanda (-) menyatakan bayangan terbalik.