Determined is defined as <span> having a strong feeling that you are going to do something and that you will not allow anyone get in your way.
Stubborn is defined as </span><span>having or showing dogged determination not to change one's attitude or position on something, especially in spite of good arguments or reasons to do so.
Connotation of determined and stubborn is being strong-willed and resolute. When you are determined, you have decided to do something. When you are stubborn, in doing what you have to do and presented with arguments, you still decided to continue what you are doing regardless of what others say.
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Hello. You did not present the excerpt to which this question refers, and you did not present the answer options. This makes your question impossible to answer. However, I will try to help you in the best possible way.
The central idea of a text is the main subject to which the text is addressing. It is the theme to which the author wishes to pass on reflection and reasoning. You will only be able to identify this idea with a complete reading of the passage to which your question refers, but you will be able to identify these ideas by the subject that the characters are addressing in their actions and speeches.
The second one. Cody and Aleena are the antecedents and <em>their</em> is the pronoun referring back to them.