求翻译：在D工序之前有两条路径，即B-D和B-C-D，由于两条路径都可以完成D工作，所以选工期短的那条路径为关键路径，B-D路径的工期为40天，B-C-D路径的工期为70天，所以B-D路径为关键路径。是什么意思？

There are two paths before in d process, namely bd and bcd, two paths can be done d, so choose a short duration of that path, critical path, the bd path duration of 40 days the bcd path duration for 70 days, bd path for the critical path.

Before operations in D There are two paths, i.e. B - D and B - C - D, because the two paths are D work can be done, so check the short construction period that path to critical path, the path D B - duration of 40 days, B - C - D path for the period was 70 days, so B - D path to critical path.

In front of D working procedure has two ways, namely B-D and B-C-D, because two ways both may complete the D work, therefore chooses the time limit for a project short that way is the essential way, the B-D way time limit for a project is 40 days, the B-C-D way time limit for a project is 70 days, t

D process, there are two paths, namely B-D and B-C-D, because the d two paths can be completed, so the path of the selected duration shorter for key path, b-d path has a duration of 40 days, 70-day duration of the B-C-D path, so B-D the path to the critical path.

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