How do you write 0.000105 in scientific notation?

To write 0.000105 in scientific notation, first identify the significant figures, which are 1.05. Then, determine the exponent by counting how many places the decimal point moves to the right to get from 0.000105 to 1.05, which is 4 places. Therefore, 0.000105 in scientific notation is (1.05 \times 10^{-4}).