An assembly line is designed like this.

WS #$1-$ ABC $-60$ sec

WS #$2-$ D

$-75$ sec

WS $-3-$ FG

$-80$ sec

WS $4-$ H

$-85$ sec

WS #$5-$ JKLM $-55$ sec

Which workstation is the bottleneck? No calculations are required for this question.

WS #$4$

$$ WS #$1$

$0$ WS #$3$

$$ WS #$2$

$$ WS #$5$