Answer:
46 terms
Step-by-step explanation:
a₁=b, a₂₁= bₙ, d₁=9, d₂=4
n=?
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a₂₁= a₁+20d₁= a₁+20*9= a₁+180
bₙ= b₁+(n-1)d₂= a₁+4(n-1)
a₁+4(n-1)=a₁+180
4(n-1)=180
n-1= 180/4
n-1= 45
n=46
2 gophers per day are getting removed
300,000/yr
52 weeks/yr
300,000/52 = 5,769.2 (rounded to the nearest tenth)