Can you write a sentence why C is the correct answer for #1 and B is the correct answer for #2?

I already know the answer I just need to know the reasoning behind it.

1. Which of these equations is NOT a valid Loop Rule equation for the pictured circuit? A) V1 - 13 R3 = 0 B) Is Rs - LAR1 = 0 C) V1 - 12 R2 + V2 = 0 D) V2 - 12 R2 - 14 RA = 0 Multiple Choice (20 points) 2. Which of these equations IS a valid Node Rule equation for the pictured circuit? A) I1 = 12 + 13 + 14.5 B) I15 = 14 + 15 C) 13 - I15 + 15 = 0 D) I1 = 12 + 13 + 14 + Is V2 M Iz R3 I 1 RX I4 m I45 LAW It , 5 Is