The following MIPS program contains two programming mistakes. The code is well- formed, and all instructions are valid MIPS instructions. Can you identify the mistakes and discuss which actions much be taken to correct them? .data str: .word 0x00000001 0x00000002 0x00000003 .text j main sum: sll $a1, $a1, 2 li $v0, 0 loop: addi $al, $a1, -4 add $t0, $a0, $al lw $s0, 0($t0) add $v0, $v0, $50 bnez $a1, loop j end main: la $a0, str li $a1, 3 jal sum end: nop