[Assuming that you've written 3.40 kg in 'a', and not 3.90 kg]
(a) 3,400 g x 0.001 = 3.40 kg [converting grams to kilograms]
(b) 220 cm x 0.01 = 2.2 m [converting centimeters to meters]
(c) 9.42 kg x 1000 = 9420 g [converting kilograms to grams]
(d) 6.53 m x 100 = 653 cm [converting meters to centimeters]
