2. [20 points] When introducing RISC-V instructions, we have seen several required formats that do not seem to follow a straightforward or convenient design. For example: (a) All arithmetic operations must have 3 operands, which makes the addition of n numbers requiring n-1 instructions. (b) The S-type RISC-V instruction format has the 12-bit immediate field split into two fields, which makes the format hard to read and understand For each of the two cases above, can you please explain, using you own words, why it is designed that way in RISC-V? 3. [40 points] Assuming variable i is in register x6, the base address of array A in memory is in register x23, and variable s is in register x18. (a) Please convert the following C code to RISC-V assembly code. Please write clear comments (using "/") to make your code easier to understand. for (i =0; i