To find the common logarithm (base-10 logarithm) of 4, we denote it as [tex]\(\log_{10}(4)\)[/tex].
Using a calculator, we find:
[tex]\[
\log_{10}(4)
\][/tex]
Evaluating the logarithm, we obtain:
[tex]\[
\log_{10}(4) \approx 0.6021
\][/tex]
Thus, rounding to four decimal places, the common logarithm of 4 is:
[tex]\[
\boxed{0.6021}
\][/tex]
