Answer from cs61c-ei (Jing Chen 16669246) for Question 2
The assembler might have problems with this expression mainly because it assumes that conditional branches will branch to a nearby instruction (less than 16 instructions away). Under PC-relative addressing, the program counter (PC) contains the address of the current instruction, allowing branching only within +/- 2^15 words of the current instruction when using the PC as the register to be added to the address. Hence, if the “there:” label was more than 16 lines away, the assembler would not be able to store the address of where to go next in it’s 16-bit address field (since PC-relative addressing uses I-format instructions for branches).