(a)
17.4 megagrams
= 17.4 Mg
= 17.4 x 1000 000 g
= 17 400 000 g

since 1000 g = 1 kg
17 400 000 g
= 17 400 kg

& in standard form
17 400 kg [shift to left 4 places ]
= 1.74 x 10⁴ kg

(b)
mass = 17 400 000 g

volume
= 1.2 x 10⁴ cm³
= 12 000 cm³

density
= mass/vol
= 17 400 000/12 000
= 1450 g/cm³

& in standard form
1450 g/cm³ [shift to left 3 places ]
= 1.45 x 10³ g/cm³

(c)
volume of 1000 cm³ cut off

mass corresponding to 1000 cm³ is
= density x volume
= 1450 x 1000
= 1 450 000 g

original mass is 17 400 000 g
cut-off mass is 1 450 000 g

remaining mass
= 15 950 000 g
= 15 950 kg
= 15.95 Mg

& in standard form
15 950 000 g [shift to left 7 places ]
= 1.595 x 10⁷ g

15 950 kg [shift to left 4 places ]
= 1.595 x 10⁴ kg

15.95 Mg [shift to left 1 place ]
= 1.595 x 10¹ Mg

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