Explanation for Question 23 From the Math (Calc) Section on the Official Sat Practice Test 6
Question 23 gives us this graph. 2 And then it asks us as part of an experiment, 3 a ball was dropped and allowed to bounce repeatedly off the ground until it 4 came to rest. The graph above represents the relationship between the time elapsed after 5 the ball was dropped and the height of the ball above the ground, 6 after it was dropped. How many times was the ball at a height of 7 two feet. Okay. So we've got our time elapsed on the X 8 axis here. So as you move in this direction, 9 the amount of time that's passed since you dropped the ball is increasing on 10 the Y axis. We have height in feet. So this is the height of 11 the ball over time. And we're trying to find out how many times was 12 the ball at a height of two feet. So our height of two feet, 13 that's right here. And we can see that wherever 14 the line passes through this height of two feet, 15 it means that these points, the ball was at a height of two feet. 16 So we can see that it intersects with that line three different times. 17 So the ball was at two feet at around. 18 Let's say that this is 0.3 seconds at around 0.7 seconds. 19 And then at around like 1.05 or 1.1 seconds. 20 So that's three separate instances. 21 So we can circle C as our answer choice.