Could you please help me find answers to these problems and provide brief explanations of each so I can understand. I appreciate all the great study support! ;-)

31.3, 1. A pure sample of the R enantiomer of a compound has a specific rotation of - A a a 15. A solution containing a mixture of the enantiomers rotated light by -4.7. What is the entantiomeric excess in the solution? 2. What is the % S enantiomer in the sample in problem 1? 3. Draw trans, (R) - 4-amino 2-octene