Can someone help me think of a cool model of a bridge to build

At an open or uncontrolled intersection, yield if a. your road is paved and the crossroad is not b. the cross road is paved and yours is not c. you have two or more passengers in your vehicle d. you did not yield in the last intersection

A911 dispatcher is the sole sender of messages to all police officers. while on patrol, officers communicate with the dispatcher who, in turn, relays messages to other officers. the officers do not communicate directly with one another. this illustrates a network.

All of the following are characteristics that must be contained in any knowledge representation scheme except