Answer:
<em>Colons</em> and <em>semi-colons</em> are breaks within sentences, stronger than a <em>comma </em>but not a full stop; due the need to separate 2 or more independent clauses, especially if the subsequent clauses explain, emphasizes, sharpens, summarizes or illustrate the first one and both are closely related.
Thereby:
<em>1. One thought...as Friday approached</em><em>: </em><em>"Please let this week be over."</em>
<em>2. Thomas Jefferson...included the following</em><em>: </em><em>life, liberty, and the pursuit of happiness.</em>
<em>3. Ander's family...different cultures</em><em>: </em><em>his mother's...Swedish, while his...Brazilian.</em>
Explanation: