Answer:
Internal; superior financial skills; self-serving bias
Step-by-step explanation:
According to Kumi, larger than average tax return is received due to some internal changes and the reason could be his extraordinary financial skills which resulted in such returns. Similarly, actions are motivated by self-biases that is why if something good happens, he tries to take all the credit for it and blames others for wrongdoings. He is a person who's thought the process is encouraged by self-esteem.