Answer:
49
Step-by-step explanation:
side 1 = |18-3|= 15
side 2 = |12-3| = 9
side 3 = |16-4| = 12
side 4: 
perimeter = 15 + 9 + 12 + 13,4= 49,4 = 49
The greatest remainder with 3 is 2, the greatest remainder with 8 is 7, and the greatest remainder with 5 is 4, all because if it was one more then it would not be remaining and it would be without a remainder. Hope this helps!
Answer:
D, supplementary, BC, D
Step-by-step explanation: