Exponatial notation is used for a/ writing very small numbers b/writing very large numbers c/avoid tedious work d/all above

The correct answer is option d/ "all above".

Explanation:

Exponential notation is a way of expressing mathematical equations by simplifying numbers that could be very small or very large. The number included within the exponential notation (the exponent) describe how many times the number included in the base is multiplied. If the exponent is an integer the number is very large, while if the exponent is a ratio the number is very small. This avoids the tedious work of writing the complete number that results from the exponential multiplication.