A tool for removing deck boards includes a base having a short shaft with a handle socket affixed thereto, and a pair of spaced prying arms connected to opposite ends of the shaft. A sub-circuit without 50-Ohm transmission line resistance is used to compute transistor bias current via a current-controlled voltage source to compensate for the DC voltage dropped across a 50-Ohm resistor contained in the network. If a counterexample is found, the bounded model checker selectively increases K and verifies the property to the new larger depth using the original constraints. In particular embodiments, the \u03b1-glucosidase substrate comprises 4-methylumbelliferyl-\u03b1-D-glucoside.