Answer
$7.8\times 10^3\;pores$.
Work Step by Step
Number of pores per square inch.
$p=6.5\times 10^2$
$a=0.12\times 10^2\;in.^2$
The number of pores is:
$=p\times a$
Substitute both values.
$=(6.5\times 10^2 pores /\;in.^2)\times 0.12\times 10^2\;in.^2$
Simplify.
$=0.78\times 10^4\;pores$
Scientific notation.
$=7.8\times 10^3\;pores$.
