<span>The answer is CTRL + A, this selects whole worksheet (A means all). In computing, a Control key is a transformer key which, when pushed in combination with one more key, achieves a singular operation (for example, Ctrl + A; like the Shift key, the Control key infrequently achieves any purpose when pushed by itself.</span>
Answer:

Explanation:
Considering the number are stored using binary notations.
If there are total 86 bits and 1 bit is used as sign bit. Then in total one can have
bit combinations since a bit can be either stored as 0 or as 1.
Therefore, the largest number that can be stored will be
.
To understand it in better way let's scale down the problem to 3 bits representation. The largest number that can be stored using 3 bits is 111 which in decimal form is 7 and is equal to
.