Answer:
" exa"
Step-by-step explanation:
str1 will create a substring of sentence from index 6 - 12
str1 = " exam "
Index 6 is the spacing between 'first' and 'exam' while index 12 is the letter 'i' of 'is'
str2 will create a substring of str1 from index 0 - 4
str2 = " exa"
Index 0 is the spacing before the 'exam' and index 4 is the letter 'm' of the ' exam'
The last position in the index is not considered when creating a substring. The substring stop a letter before the last index given as argument