Read the following sentence. The cake that I baked last night is already gone. Is this an example of nonrestrictive or restrictive clause? please i need answers

Which of the following is not one of the part of speech

Read the sentences. the lowest point in antarctica appears to be the bentley subglacial trench, which is 8,200 feet below sea level. lower points may exist. which choice correctly uses the subordinating conjunction “although” to combine the sentences? the lowest point in antarctica appears to be the bentley subglacial trench, which is 8,200 feet below sea level, although lower points may exist. the lowest point in antarctica appears to be the bentley subglacial trench, which is 8,200 feet below sea level. although lower points may exist. the lowest point in antarctica appears to be the bentley subglacial trench, which is 8,200 feet below sea level although, lower points may exist. the lowest point in antarctica appears to be the bentley subglacial trench, which is 8,200 feet below sea level; although lower points may exist.

Need on this. its about integrating sources, quoting, and paraphrasing. (free 15 points! < 3)