Three engineering teams A, B, and C complete a certain project independently. Respectively need 140 hours, 87.5 hours, 77 (7/9) hours. Now, both A and B can only work for 60 hours at most, and C can only work for 35 hours at most, and the sum of the working hours of the three teams is 100 hours to complete the project, so how many hours can A work at most?
甲、乙、丙三个工程队单独完成某项工程．分别需要140小时、87.5小时，77(7/9)小时．现在，甲和乙都最多只能工作60小时，丙最多只能工作35小时，三队工作时间之和为100小时完成工程，则甲最多工作多少小时？
<result>45</result>