Answer:
8 × 10¹
Step-by-step explanation:
don't panic. just breathe deeply and then think logically.
0.002 ... what is that ? 2 10ths ? 2 hundredths ? 2 thousandths ? 2 tenthousandths ?
the 3rd position after the decimal point is for 1/1000.
and that means 10^-3. in the same way as 1000 is 10³.
so, it is 2 × 10^-3.
the other rounded number is then 4 × 10⁴.
now, we are multiplying both numbers
2×10^-3 × 4×10⁴
what do we do ?
we combine the same types of factors, like the basic constants : 2×4 = 8
and 10^-3 × 10⁴.
what hairball when we multiply the same base number with exponents ? we add the exponents :
10^-3 × 10⁴ = 10¹ = 10
because -3 + 4 = 1
and so, the result is
8 × 10¹