Answer:
a) since they have a common angle and
Other two sides are in the same ratio, they are similar by SAS similarity theorem.
40/20 = 30/15 = 2
Therefore ABC is similar to DEF
b) Volume of a prism
= base area × height
Let height be 'h'
With Base ABC:
Volume = ½×20×15×h = 150h cm³
With Base DEF:
Volume = ½×40×30×h = 600h cm³
600h/150h = 4
Prism with base DEF has a greater volume; it's 4 times of the volume of the prism with base ABC