Space between staves in a staff group

I have a short passage (6 measures) of a trumpet duo. I am using a staff group for the two trumpet staves. How do I increase the vertical distance between the two staves? Phil Hanna

How to show split stems

I have a measure with two notes on the same line of the staff, a D natural and a D sharp. I'm trying to figure out how to have the stems split as shown in the image, but I can't find anything obvious in the documentation. Thanks f