ILL MARK YOU BRAINLIEST IF YOU ANSWER CORRECTLY

Write in scientific notation: 0.0042
A) 42 x 10^-2
B) 4.2 x 10^-4
C)4.2 x 10^-3
D).42 x 10^-4
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write in standard notation:6.12 x 10^3
A)6120
B)612
C) 61,200
D)61.2