The spelling of the word "palko" is determined by its pronunciation. In IPA phonetic transcription, it is represented as /pælkoʊ/. The first syllable "pal" is spelled with the letter "p" and the vowel sound is represented by "æ". The second syllable "ko" is spelled with the letter "k" and the vowel sound is represented by "oʊ". "Oʊ" is a diphthong, which means it contains two vowel sounds. Thus, the correct spelling of "palko" must include "p", "a", "l", "k", "o" and "w" to signify the "oʊ" sound.