..Module 13 describes how the SparcV8 processor makes use of "register windows". Recall that when one function calls another, the called function can execute the Sparc "save" instruction to slide the window so that a new set of registers can be accessed within the called function. The table below shows the names assigned to each of the 32 Sparc registers that can be accessed by a function or procedure. The global registers (%g0 to % g7) are accessible to all functions. The remaining 24 registers are treated like logical registers each of which must be mapped to one of the physical hardware registers. Recall that adjacent register windows overlap. Register names Register numbers %g0 - %g7 %r0-%r7 %00 - %07 %r8 - %r15 %10 - %17 %10 - %17 %r16 - %r23 %r24 - %r31 a) (3) What is the main advantage of using register windows? b) (3) If the system allows only two register windows, what is the total number of physical CPU hardware registers required for the system?