Of the following, is the smallest mass. 2.5 ×10^−2 mg
25 kg
2.5 ×10^15 pg
2.5 ×10^9 fg
2.5 ×10^10 ng

25kg is the largest mass.

Explanation:

Convert all the masses to kg so that the units would be uniform

1mg = 10^-6kg

2.5×10^-2mg = 2.5×10^-2×10^-6 = 2.5×10^-8kg

1pg = 10^-15kg

2.5×10^15pg = 2.5×10^15×10^-15 = 2.5kg

1ng = 10^-12kg

2.5×10^10ng = 2.5×10^10×10^-12 = 0.025kg

1fg = 10^-18kg

2.5×10^9fg = 2.5×10^9×10^-18 = 2.5×10^-9kg

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