A force acts during the $1.8$ s interval that begins $0.7$ s after an experiment starts. What are the correct integration limits?

• A. $t_1=0$ s, $t_2=1.8s$
• B. $t_1=0.7$ s, $t_2=2.5$ s
• C. $t_1=1.8$ s, $t_2=2.5$ s
• D. $t_1=0.7$ s, $t_2=1.8$ s

Answer: (B)