Answer:
[tex]C\text{ ; 2.8 }\times\text{ 10}^{-4}[/tex]Explanation:
Here, we want to get the expression that is equal to the given value
Mathematically, we have it that e represents the power of 10 in cases like this
Thus:
[tex]2.8\text{ E}^{-4}\text{ is the same as 2.8 }\times\text{ 10}^{-4}[/tex]