Use the Following T Account to Answer the Questions Below

Essay

Use the following T account to answer the questions below (assume a calendar-year accounting period).
$\begin{array}{l}\text { Allowance for Uncollectible Accounts }\\\begin{array}{rr|lr}\hline 1 / 10 & 300 & 1 / 15 & 300 \\5 / 12 & 440 & 12 / 31 & 3,600\end{array}\end{array}$ What apparently occurred on:
a. January 10?
b. January 15?
c. May 12?
d. December 31?