1) The document describes a circuit designed to implement adaptive voltage scaling. It uses a ripple carry adder, frequency monitor, and voltage scaling logic. 2) Simulation results show the adder's frequency is 125MHz at 3.3V and 40MHz at 1V. The frequency monitor uses a binary counter to measure the adder's speed. 3) Rather than scaling voltage based on frequency, the final implementation scales voltage according to an input mode selection. Running simulations for different modes shows how supply voltage and adder speed vary.