(1)5千克=5000克;
(2)46厘米=0.46米;
(3)456克=0.456千克;
(4)6米90厘米=6.9米;
(5)2千克600克=2.6千克;
(6)7元4角8分=7.48元.
故答案为:5000,0.46,0.456,6.9,2.6,7.48.
(1)5千克=5000克;
(2)46厘米=0.46米;
(3)456克=0.456千克;
(4)6米90厘米=6.9米;
(5)2千克600克=2.6千克;
(6)7元4角8分=7.48元.
故答案为:5000,0.46,0.456,6.9,2.6,7.48.