英文正負數...急!!!

1.At the beginning of the year, Healthy Company had a cash balance of $180 000. The company made a loss of $40 000 monthly for the first five months, and then started making a profit of $15 000 monthly for the rest of the year.
In the same year, Lively Company had a cash balance of $200 000 at the beginning. the company made a profit of $5 000 monthly for the first three months, and then started making a loss of $30 000 monthly for the rest of the year.
(a)At the end of April, how much cash was left with Healthy Company and Lively Company each?
(b)At the end of August, which company had more cash left?
(c)Cheerful Company had a cash balance of $220 000 at the beginning of the year. At the end of August, the cash balance of the company is the same as that of Lively Company. If Cheerful Company made the same amout of profit/loss monthly for the whole year, what was the amount of monthly profit/loss made by the company?

2. 4 people played cards for 5 rounds. In each round, there is 1 winner, and the marks got by the winner equals the total marks lost by the losers. It is known that the marks lost and got are represented by a negative number and a positive number respectively. The following table shows the accumulated marks at the end of each round.
Mike John Danny Stephen
Round 1 -5 -4 (we don't know) +33
Round 2 -13 -11 -3 +27
Round 3 -21 -17 +47 -9
Round 4 -43 +49 +25 -31
Round 5 -50 +89 +1 -40
(a)Who was the winner in the 1st round? How many marks did Danny lose?
(b)Who was the winner in the 2nd round? How many marks did he get?
(c)How many marks did Stephen lose in the 3rd round?
(d)How many rounds did each of them win?

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