A. The Server 2008 R2 implementation of Hyper-V adds support for SLAT, which is a feature in the newest versions of the Intel and AMD processors, where it's known as Extended Page Tables (EPT) and Nested Page Tables (NPT) respectively. With SLAT, the processor handles the mapping of virtual machine memory to physical memory instead of the hypervisor.
To check if SLAT is being used, you can look at the Hyper-V Hypervisor Root Partition counter group and the Address Spaces counter. If SLAT is being used, the Address Spaces counter will be 0, as this picture shows.
If SLAT isn't being used, a value will be present, as this picture shows.