With virtualization, virtual machines can share more than available physical memory through various methods. It also affects the distribution of CPUs. However, there is a limit to how much physical resources can be exceeded by allocating virtual memory and CPU to virtual machines

a$.$ Explain the concept of virtual memory in the context of virtualization.$[3$ marks$]$

b$.$ Describe two methods through which virtual machines can share more memory than is physically available.$[4$ marks$]$

c$.$ Discuss how CPU resources are distributed in a virtualized environment. How does virtualization affect CPU allocation?$[3$ marks$]$

d$.$ Explain the limitations of exceeding physical resources, such as memory and CPU, when allocating them to virtual machines. What challenges might arise when these limits are approached? $[4$ marks$]$