On the other hand, standard, or open pollinated varieties are more or less stabilized in their characteristics. They remain fairly consistent, producing seed that will grow into plants more or less like their parent plants, though less uniform than hybrids.
The rank of admiral (or full admiral, or four-star admiral) is the highest rank normally achievable in the U.S. Navy. It ranks above vice admiral (three-star admiral) and below fleet admiral (five-star admiral). There have been 262 four-star admirals in the history of the U.S. Navy. Of these, 221 achieved that rank while on active duty, 40 were promoted upon retirement in recognition of combat citations, and one was promoted posthumously.
The U.S. Navy has the world's largest aircraft carrier fleet, with ten in service, four in the reserve fleet, and three new class carriers under construction. The service has 328,186 personnel on active duty and 110,882 in the Navy Reserve.he United States Navy (USN) is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is currently the largest, most powerful navy in the world, with the highest combined battle fleet tonnage.