If you are reading this in an email you received from me, do not click the link to sat.collegeboard.org below. Use the link to my website that is farther down on the email. If you are seeing this in my blog, do the SAT Question of the Day by clicking on this link:
http://sat.collegeboard.org/practice/sat-question-of-the-day?src=R&questionId=20130517 (This link takes you to today’s question. If you use my archive, you will see the question related to my SAT explanation for that date.)
The answer is B. For Sentence Completion questions, always 1) figure out the topic, 2) use key words and phrases, 3) apply internal punctuation (commas, semicolons, etc.), and then 4) make a prediction for the blank(s) prior to looking at the answers.
For this question, you can see that the topic is that there is a usual definition of rock that geologists (a short pause here to remember my dad who was one) “add to” (my prediction for the second blank) so that clay, etc. is included. The first blank is about rocks being a “combination” of minerals; so, I predicted “combination” for the first blank. (There’s nothing wrong with using a word that signals the topic from the sentence as the predicted word for the blank! In fact, doing so makes getting the right answer easier.) I used my prediction for the second blank, “add to” to eliminate as many answers as I could. Only answer B, “extend,” worked. All the other answers were eliminated. I saved the time of worrying about the words for the first blank. That was fun. Finally, I looked at the first word for answer B and sure enough “aggregate” means “combination.” All done.
Let’s see what kind of “wizardry” we can use to answer the ACT question.
http://www.act.org/qotd/ (The ACT staff does not put a date on their questions so if you click on an archived blog, you’ll get today’s question and the old explanation. Sorry. The SAT staff has dated their questions; so, the archive is helpful. The ACT folks simply don’t do that.)
The answer is G. It is the only answer that is consistent with the topic of the paragraph. As you are reading the passage, the topic is that radio was a simple tool for communicating between people: ham operators, pilots, etc. Then, we get a sentence that tells us the “vast potential” hasn’t been touched. The only transitional word that makes sense is “however.” The others, including the original “therefore,” don’t make sense. We need a word that tells us there is an anomaly between the current condition and the “vast potential.” “However” does that.
I hope your day goes well as you move into “final exam season.” Start reviewing if you haven’t already done so.