How do solve 2 SAT problems?

Test Preparation SAT Preparation
1

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<li><p>Alan and Ben each run at a constant rate of 7.5 miles per hour. Carla runs at a constant rate of 10 miles per hour. Debby runs at a constant rate of 12 miles per hour. In a relay race with these four runners at a team running one right after the other, Alan runs 0.3 miles, then Ben runs 0.3 miles, then Carla runs 0.5 miles, then Debby runs 0.24 mil.es. What is the team’s average speed in miles per hour?</p></li>
<li><p>If -1 is less or equal to a and a is less or equal to 2, what is the greatest possible value of (a+b)(b-a)</p></li>
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2

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<li>Distance = rate (mph here) x time</li>
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<p>So just add up the combined distance that the A,B,C,D dudes run, and then divide it by the total time it takes them. </p>

<p>Now the power is in your hands to figure the problem out (my being lazy is a factor as well).</p>

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<li>Did you write the question right? Is there a restriction on b?</li>
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