Answer: Please refer to explanation.
Step-by-step explanation:
Since it is an Available for Sale debt, we journalize it as follows
2018
Dec. 31
DR Unrealized holding loss on AFS 600
CR .Fair value adjustment - AFSI 600
(To record available-for-sale investments at fair value)
Calculation,
= Cost Price - Market Price
=($3000 - $2400)
= $600
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