Can you provide some NMR practice problems for me to work on?

Here are a few NMR practice problems for you to work on:

1. Identify the number of unique hydrogen environments in the molecule C6H12O2.
2. Determine the chemical shift values for the following peaks in a 1H NMR spectrum: 1.2 ppm, 2.5 ppm, and 4.0 ppm.
3. Predict the splitting pattern for the hydrogen atoms in the molecule CH3CH2CH2CH3 in a 1H NMR spectrum.

These problems should help you practice your NMR skills. Good luck!