d) There is one program running on an 500MHz processor. The executed program contains: 5 million R-class instructions and each R-class instruction needs 3 clock cycles; 4 million I-class instructions and each I-class instruction needs 5 clock cycles; 1 million J-class instructions and each J-class instruction needs 4 clock cycles. i) Calculate the average CPI. Explain its meaning. ii) Calculate the MIPS rate. Explain its meaning. iii) Calculate the CPU execution time for the given processor. Explain its meaning