For the first part, we know that we start at 1500$. Next, we know that we have 100% of the 1500$ at the start. After that, it depreciates at 30%, so we have (100-30)%=70%, and 70/100=0.7, so it multiplies by 0.7 every year, and the answer is either the second or third one. For the second part, we know that we start at 1500 dollars - it cannot go higher than that, but it has to be that at the start (x=0, or no time has passed). Next, we subtract 300 for every year, so after x years, it has depreciated 300*x times. Therefore, for the amount of money it's worth, we have y=1500-300x and the answer is the third option
Feel free to ask any questions that come up!
