题目

City College Union Inc Secretary/Typist The Union is a student-run organization with a permanent staff of 20.Typing  speed:at least 60 wpm. The ability to take shorthand dictation and a working knowledge of filling procedures are essential requirements. The basic salary for the position is $ 18,500 per year. Enquires to R.Barbar 387-5075. Emu Airline Secretary Emu Airline is now offering a part-time position for a secretary. The position offers at least 20 hours’ work a week, with a view to full-time work in the future. Monthly salary is about $ 1,400. Phone 899-3264 for an appointment. 如图所示，△ABC，D，E，F三点将BC四等分，AG：AC=1：3，H为AB的中点，下列哪一个点为△ABC的重心（　　）A．XB．YC．ZD．W