Suppose a computer has 16-bit instructions. The instruction set consists of 32 different operations. All instructions have an opcode and two address fields (allowing for two addresses). The first of these addresses must be a register, and the second must be memory. Expanding opcodes are not used. The machine has 16 registers. What is the maximum allowable size for memory

2^7= 128

Explanation:

An instruction format characterizes the diverse part of a guidance. The fundamental segments of an instruction are opcode and operands. Here are the various terms identified with guidance design:  Instruction set size tells the absolute number of guidelines characterized in the processor.  Opcode size is the quantity of bits involved by the opcode which is determined by taking log of guidance set size.  Operand size is the quantity of bits involved by the operand.  Guidance size is determined as total of bits involved by opcode and operands.