If `Delta ABC~Delta EDF and Delta ABC` is not similar to `Delta DEF` then which of the following is not ture ?

triangle ABC ~ triangle DEF is given then which of the following is correct.

Delta ABC is similar to Delta DEF . The ratio of their perimeters is 4 :1 The ratio of their areas is

Delta ABC ~ Delta EDF and area (Delta ABC) : Area (Delta DEF)=1:4 . If AB = 7cm, BC = 8 cm then DF=?

If Delta ABC-Delta DEF,BC=3cm,EF=4cm and area of Delta ABC=54sqcm then find the area of Delta DEF

If Delta ABC ~ Delta DEF such that area of Delta ABC " is " 9 cm^(2) and the area of Delta DEF " is " 16 cm^(2) and BC=2.1 cm. Find the length of EF.