Question

What is the capacity of a tank in the shape of an open glass cubiod 30cm deep with a base 16cm by 17cm , these measurements being external if the glass is 0.5cm thick

Answer 1

cuboid perhaps?

inner dimensions:
since it is open, the sides are (16 - 2(.5)) by (17 - 2(.5)) by (30 - .5)

multiply these to get the volume.