Cho X là biến ngẫu nhiên rời rạc có bảng phân phối xác suất x 1 2 3 4 5 6 7
P a 2a 2a 3a a² 2a² a(7a + 1)
a. Xác định tham số a.
b. Với a tìm được, tính P(X≥4).
c. Tìm kỳ vọng và phương sai của X.

What two elements normally must exist before a person can be held liable for a crime

Acompany using the perpetual inventory system purchased inventory worth $540,000 on account with credit terms of 2/15, n/45. defective inventory of $40,000 was returned 2 days later, and the accounts were appropriately adjusted. if the company paid the invoice 20 days later, the journal entry to record the payment would be

Robert black, regional manager for ford in texas and oklahoma, faced a dilemma. the ford f-150 pickup truck was the best-selling pickup ever, yet ford's headquarters in detroit had decided to introduce a completely redesigned f-150. how could mr. black sell both trucks at the same time? he still had "old" f-150s in stock. in his advertising, mr. black referred to the new f-150s as follows: "not a better f-150. just the only truck good enough to be the next f-150." this statement represents ford's of the new f-150.