Answer :
Answer:
Gregor and Isabelle
Step-by-step explanation:
We have the runner time compared to personal best for [tex]5[/tex] persons i.e. Gregor [tex]+5.6[/tex], Hiroki [tex]-11.6[/tex], Isabelle [tex]+3.2[/tex], Juan [tex]0[/tex], and Karen [tex]-5.2[/tex].
As [tex]\text{speed} = \frac {\text {distance}}{\text {time}}[/tex], so, for a fixed distance, if anyone taking more time then personal best than that person is slower.
Here, Gregor and Isabelle taking more time, so, they ran slower than their personal best.