A combustor includes a combustor head with an integrated counter-flow heat exchanger. A table of mantissa and exponent values is created for a sufficient range of values for 1a. The plugless locking system has a first plugless lock is configured to receive an external trim and is configured to mate with a second plugless lock. The chromene compound has a naphthopyran cyclic skeleton, and is expressed by, for example, the following formula in which a substituent such as substituted amino group or morpholino group is bonded to the sixth position of the naphthopyran ring through a nitrogen atom, and two aryl groups having a particular substituent are bonded to the third position thereof, 1. Once enabled, the replica controller virtual machine may be operated without suspension of the source controller virtual machine. To do so, a fee equal to thirty percent of the double down bet must be placed on the double assurance line so provided.