Assess students' ability to convert between binary, hexadecimal, and decimal (both unsigned and two's-complement), perform fixed-width binary addition and subtraction, and detect/sign-extend and explain overflow or underflow. Problems should require showing conversion steps, computing results in binary and an alternate base (hex or decimal), and stating whether overflow occurred for a given bit width. Scope: 4–6 medium-difficulty applied tasks suitable for grades 9–12.