According to the definition of scientific notation, the expression of scientific notation is a× 10 n, where 1 ≤| A | < 10, and n is an integer. It is very important to correctly determine the value of a and the value of n when expressing. When determining the value of n, see whether the number is greater than or equal to 1 or less than 1. When the number is greater than or equal to 1, n is its integer digits minus1; When the number is less than 1, -n is the number of zeros before its first significant number (including 1 zeros before the decimal point). 86.54 billion = 8654000000, with a total of 1 1 bit, so 86.54 billion = 8654000000 = 8.654×10. The number of significant digits is calculated by starting with the first digit on the left that is not 0, and all subsequent digits are significant digits. Therefore, 86.54 billion = 865400000 = 8.654×1010. ≈8.65× 10 10 。 So choose C.