Identify by Marking an X in the Appropriate Column, Whether

Identify by marking an X in the appropriate column, whether each of the following items would likely serve as a source document. The first one is done as an example
$\begin{array} { | c | c | c | c | } \hline & & \text { Yes } & \text { No } \\\hline \text { Ex. } & \text { Credit card } & & \mathrm { X } \\\hline \text { a. } & \text { Credit card receipt } & & \\\hline \text { b. } & \text { Purchase order } & & \\\hline \text { c. } & \text { Invoice } & & \\\hline \text { d. } & \text { Balance sheet } & & \\\hline \text { e. } & \text { Bank statement } & & \\\hline \text { f. } & \text { Journal entry } & & \\\hline \text { g. } & \text { Telephone bill } & & \\\hline \text { h. } & \text { Employee earnings record } & & \\\hline\end{array}$