Answer:
Period    Bonds        Interest    Cash        Increase in        Bonds payable
              Payable     Expenses   Paid       Bonds payable     at the end
2018     583352      23334.08   18000         5334.08          588686.1
2019     588686.1    23547.44   18000         5547.44          594233.5    
2020    594233.5   23766.48   18000         5766.48          600000
Journal entries
<u>Jan 01 2018</u>
Cash account	Dr $583352
Discount on Bonds Payable Dr $16648
Bonds payable Cr $600000
<u>Dec 31 2018</u>
Interest expense Dr $23334.08
Cash account Cr $18000
Discount on bonds Payable Cr $5334.08
<u>Dec 31 2019</u>
Interest expense Dr $23547.44
Cash account	Cr $18000
Discount on bonds Payable Cr $5547.44
<u>Dec 31 2020</u>
Interest expense Dr 23766.48
Cash account Cr $18000
Discount on bonds Payable Cr $5766.48
<u>Dec 31 2020</u>
Bonds Payable Dr $600000
Cash account	Cr $600000
<u>01.01.2020</u> (Redemption at 101)
Bonds Payable Dr $600000
Loss on redemption of bonds Dr $11766.48
Cash account (600000*101%) Cr $606000
Discount on bonds payable Cr $5766.48