How may bit strings are there of length 8

there are 256 bits. there 256 values u can store in a byte

different strings

Explanation:

A bit can either store a 1 or a 0, this gives you 2 different 1-bit strings (0, 1), 4 different 2-bit strings (00, 01, 10, 11), and in general, strings for an n-bit string. Why ? Well, for every bit, we have 2 choices, either a 0 or a 1, which means we double the number of possible strings with every additional bit. So, in a string with a length of 8 bits, we'll have possible choices for strings.

yes we can change both the color of the value of a cell as well as background color of a cell at the same time .

as we know that excel sheet consists of columns and rows.

and intersection of column and row is called cell.

we can change color of the cell and background of the cell at the same time.

hence the statement that

can a person change color of the cell and background of the cell at the same time is true.

yes you can contact there email