Final answer:
The Oak-Leaf cluster comes in two sizes, a larger size (1 3/32 inch) for full-sized medals and a smaller size (5/16 inch) for ribbons, representing multiple awards of the same military decoration. Plants like the pin oak have branches extending at different angles from the main stem.
Step-by-step explanation:
The Oak-Leaf cluster is a symbol used in the military to denote additional awards of the same decoration. Regarding the sizes of the Oak-Leaf cluster, there is a larger size (1 3/32 inch) and a smaller size (5/16 inch). These devices are worn on military ribbons and medals to signify multiple instances of receiving a particular award. The size of the cluster may vary depending on the uniform regulations or the particular medal to which it is affixed. When it comes to plant branches, as a point of comparison, some plants like the pin oak have branches that extend roughly 90 degrees from the main stem, while others grow at a more acute angle, closer to 45 degrees.