Questions on standard form 2

1: --[reporting2] Doing 'do snippet' - should be imbed--

Express this number in standard form:
27,540,000,000

2: --[reporting2] Doing 'do snippet' - should be imbed--

Express this number in standard form:
0.000 000 0678

3: --[reporting2] Doing 'do snippet' - should be imbed--

Express this number in standard form:
0.0123

4: --[reporting2] Doing 'do snippet' - should be imbed--

Express this number in standard form:
765 x 10¹⁴

5: --[reporting2] Doing 'do snippet' - should be imbed--

What is 9 x 10⁴ x 12 x 10³?