A recursive rule for a geometric sequence:

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The exciplit rule:

Substitute:

Multiply 40x7 then subtract that total you got from multiplying 40x7 with 420
40x7=160
420-160=260
260 pieces of wood were left.
-(-8+5)+(-4+(-7+(-9-5)+3))
-(-8+5)+(-4+(-7+(-14)+3))
-(-8+5)+(-4+(-7-14+3))
-(-8+5)+(-4+(-18))
-(-8+5)+(-4-18)
-(-3)+(-22)
3+(-22)
3-22
19
Answer:
I would just guess, but if i were to actually think about it, i would think C. I hope it helps, and blame it on me if you fail.
Step-by-step explanation: