23 × 536 = 12328
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Answer:

Step-by-step explanation:
Lines form 180 degrees on either side. The negative sign simply implies direction (clockwise instead of counter-clockwise), which is negligible as 180 is exactly half of 360 so you'd form the same line.
15. -2
16. A. The pool was originally empty
Answer:
Fastest to slowest = 6.08 > 6.4 > 6.72 > 6.75 > 7.03
Step-by-step explanation:
The person who completes the 50-meter race within the shortest possible time is the fastest sprinter. Here, the third sprinter crossed the line in 6.08 seconds, whereas the 4th sprinter crossed the line in 7.03 seconds. That is why the third sprinter has won the race, and he becomes the fastest. On the contrary, the fourth person takes the most time to complete the race, meaning he is the slowest.