Step-by-step explanation:
 This is a ratio problem
 Vol cone = 1/3 π r² h
Cone S is 768pi cm3
Cone T is 6144pi cm3
Cone S and cone T are similar I think this means they have the same radius
   Vol cone S  =  1/3 π r² hs   Vol cone T  =  1/3 π r² ht
   Vol  Cone S /  Vol Cone T   =   1/3 π r² hs / 1/3 π r² ht
  Vol  Cone S /  Vol Cone T   =   hs /  ht                 Â
        768 / 6144  =  hs / 24    (note the π cancelled out
        h cone s = 768(24) / 6144
        h cone s =  3 cm