URGENT!!! Result only not explain the solution please

In the working set model, the idea is to examine the most recent A page references. It is also known as an approximation of the Program's Locality. If the total demand is greater than the total number of available frames (D>m), then it will cause thrashing, because in this case, some processes will not have enough frames. Below you see 3 processes and their expected memory references during their execution. When will the thrashing happen to occur according to the Working set model? Assume total memory (m) is 14 and Delta (A) is 5. Time: 1 1 2 3 4 7 8 9 10 11 12 13 14 15 16 17 P1= 26 2 2 6 2 6 2 1 2 4 3 5 4 5 4 6 P2= 7 8 6 1 8 6 7 9 4 9 8 7 6 9 9 9 9 P3= 6 2 3 2 6 6 6 6 6 2 1 4 2 2 2 2 2 Yanit