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Consider a VM hypervisor for running operating systems (OS1 and OS2) on top of it inside two virtual machines: a). The scheduler of the VM hypervisor has just granted OS1 CPU time for 20ms. While OS1 is running in the granted time slot, the timer of OS2 for triggering the CPU scheduler of OS2 expires. Describe two different options of how the VM hypervisor could deal with this! Note: Assume a single processor/single core system: this means, while the VM hypervisor is executing OS1, OS2 is suspended. Also assume that a native hypervisor and no paravirtualisation are used and therefore, the guest OSes do not know that they are running in a VM nor does the hypervisor know internals of the guest OSes. Do not discuss CPU scheduling algorithms in general, but consider just two different options for the particular scenario above (=what to do if an external interrupt occurs which is intended to be serviced by a VM which has currently not the CPU). b). In a virtual machine scenario, the different virtual machines are really completely separated from each other: OS1 running on VM1 can neither access the main memory nor the 1 files1 of OS2 running on VM2. Describe one possible solution that allows you nevertheless to exchange data between different virtual machines