Brooks Co$.$ purchases debt investments as trading securities at a cost of $$66,000$ on December $27.$ This is its first and only purchase of such securities$.$ At December $31,$ these securities had a fair value of $$72,000.$

Prepare the December $27$ entry for the purchase of debt investments.

Prepare the December $31$ year$-$end fair value adjusting entry for the trading securities$\text{'}$ portfolio.

Prepare the January $3$ entry when Brooks sells a portion of its trading securities $($costing $$3,000)$ for $$4,000$ cash.