i.e. Level 4:
Earning Rate - 0.00002 BTC/min
Max Capacity - 0.009 BTC
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Max Monthly Income: "0.864 BTC"
Upgrade (costs): 0.25 BTC
Reach Max Capacity: 0.009 / 0.00002 = 450 min => 7.5 hours
In 22.5 Hours - 0.027 BTC (three harvest in time)
+ In 1.5 Hours - 0.00188 (small harvest)
In a day (earning): 0.027 / 22.5 * 24 = 0.0288 BTC
In a month: 0.0288 BTC * 30 days = "0.864 BTC" ----
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Now:
Lifetime - 17 days 08:40:00
Earning: 0.0288 BTC * 17(º) days = 0.4896 BTC
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