30 similar houses are to be built in a housing project. For each house, 10 trade activities need to be carried out, and their relationships are given in the following network diagram. The duration of each trade activity for one house is listed in the table. 

Assume all the trade activities need to be carried out continuously and the total project needs to be finished in the shortest possible time.

(1) Calculate the total duration, starting week and finishing week for each trade using the LOB method.

(2) Determine the total project duration.