B is the answer cudijfjdjsksks
You can solve the problem this way:
Your money is increading $6 a week while sister's is decreasing $7 a week (because she isn't saving any and is spending $7 of what she has weekly)
Your money each additional week vs sister''s:
80/145 (Week 0)
86/138 (Week 1)
92/131 (Week 2)
98/124 (Week 3)
104/117 (Week 4)
110/110 (Week 5) The amounts are the same in 5 weeks.
