Hyper-focusing for the SAT/ACT

In a recent tutoring session with one of the bright juniors I work with, we were discussing the following ACT problem:

The student had answered E. 2,700. Did you catch the student's mistake?

Presented in isolation, this problem may not seem too difficult. But imagine having to pay attention to the details in a problem like this when it's the 47th problem in the second section of a three-and-a-half-hour-long exam. Unsurprisingly, by the time my student got to this question, even the italicized yards wasn't enough to make her notice that there was a shift in the units of measurement here. She fell into an all-too-common trap of not really reading what the question is asking for.

Now let's put your focus to the test one more time. How many times does the letter “F” appear in the following sentence?