Abstract: The method and system include presenting a user with a plurality of questions, timing the user's response time for the plurality of questions, identifying an optimal answer time where the user is able to answer a maximum percentage of questions correctly, and informing the user of the optimal answer time. An embodiment of the method may also include providing the user with a suggested change in an actual time taken to answer a question. Certain embodiments may also include weighting the chance of receiving a question in a particular topic based on the user's past performance in answering questions in that topic.

Abstract: A gaseous and liquid fuel injection valve for an internal combustion engine comprises an injection valve body that houses two separate concentric fuel injection valve assemblies. The first valve assembly is a pilot fuel needle valve assembly, which comprises a first needle movable in the direction of the longitudinal axis of the body between an open and a closed position. The second valve assembly is a gaseous fuel needle valve assembly, which comprises a second needle movable in the direction of the longitudinal axis between an open and a closed position. The gaseous fuel needle valve assembly controls the injection of gaseous fuel into the combustion chamber through a plurality of gaseous fuel holes formed in a nozzle tip of the gaseous fuel needle valve assembly. At least one of the nozzle tips is rotatable to thereby change the position of the pilot fuel holes with respect to the gaseous fuel holes.