Final answer:
Sarah's answer is incorrect because she used an incorrect format when using the calculator to find the sine of 125 degrees.
Step-by-step explanation:
When Sarah wrote down 'sin sin125 degrees.57', it is clear that there is a misunderstanding of how to use the sine function on the calculator. The correct way to find the sine of 125 degrees on a calculator is to simply input 'sin 125' and press the appropriate button. The calculator will then display the correct value. In this case, Sarah should expect to see a value close to 0.819.