What is the mantissa in -1.58E5?

This question asks about the mantissa in the number -1.58E5.

Let's break down what mantissa means:

In scientific notation, a number is written as a decimal number multiplied by a power of 10. For example, -1.58E5 is the same as -1.58 x 10⁵.

The mantissa is the decimal number part (the part before the 'E') of the scientific notation.

In this case, the mantissa is -1.58.

So the correct answer is Option A: -1.58.