Q. What is a net ? A. The circuit diagram of a device is a network of wires. We call an individual wire a net. Q. Do we need to understand the Booth Multiplier ? A. The idea behind it (base-four multiplication) is sufficiently simple that you would be expected to know it and to be able to sketch out various implementations from first principals. The same can be said for conventional, base-two, long multiplication and long division. Q. Do we need to understand the Kogge Stone adder ? A. Not in detail: just to understand that certain adder designs might be better in full custom and others better when synthesised from a semi-custom cell library.