charlzperru4498 charlzperru4498 09-02-2024 Mathematics contestada What is the numerical value of (2.1 x 10⁴)(4.0 x 10⁻²)? 1) 8.4 x 10⁻² 2) 8.4 x 10² 3) 8.4 4) 8.4 x 10⁻⁸ 5) none of the above