Answer:
8.6 × 10-4
Explanation:
All numbers in scientific notation or standard form are written in the form m × 10n, where m is a number between 1 and 10 ( 1 ≤ |m| < 10 ) and the exponent n is a positive or negative integer. Therefore, the decimal number 0.00086 written in scientific notation is 8.6 × 10-4 and it has 2 significant figures.