Problem $4$: $(7$ points$)$ Below is one of you classmate's work. Was your classmate's work correct? If it is

incorrect, describe the error and fix the error.

$lo{g}_{2}8=lo{g}_2(4+4)$

$=lo{g}_{2}4+lo{g}_{2}4$

$=lo{g}_2{2}^2+lo{g}_2{2}^2$

$=2+2$

$=4$