Convert these numbers between standard form and normal numbers

Question 1:

2.43× 10 5
243000

Question 2:

3.45× 10 6
3450000

Question 3:

2.91× 10 -2
0.0291

Question 4:

2540
2.54× 10 3

Question 5:

6300000
6.3× 10 6

Question 6:

0.000633
6.33× 10 -4