Help me with this math problem pls

Answer:
Your answer would be D
Step-by-step explanation:
All you need to do is subtract by ten till you get to -10
Please mark as brainllest have a nice week
[o]-[o]
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Answer:
C
Step-by-step explanation:
it is clearly decreasing as each day passes which eleminates answer choice A & B.
between monday & tuesday it decreases by 15.
between tuesday & wednesday it decreases by 10.
between wednesday & thursday it decreases by 5.
so answer choice C (decrease 10) is clearly the better answer choice over B (decrease 30).