It'll be the only one they get. K is for knowledge. Become a perpetual student. Learn all you can about the profession of selling and the customers you serve. Remember, knowledge is the ultimate equalizer.
E is for effectiveness.
Would you rather be effective or efficient. How you respond can have a huge impact on your performance. Being effective is doing the right thing. Proactive people prioritize everything. If you want to know how a person spends his money examine his checkbook.