It is 334 in standard notation.
1.656 in Scientific Notation = 1.656 x 100
1.77 x 100 is already in scientific notation. The same figure is 1.77 in standard notation.
334 = (3 x 100) + (3 x 10) + (4 x 1)
6.72 x 109 in standard notation = 6,720,000,000
7.54 x 105 in standard notation = 754,000