[求助]朋友们帮忙看看几道数学题，谢谢

xxsc

1.For a finite sequence of nonzero numbers, the number of variations in sign is defined as the number of pairs of consecutive terms of the sequence for which the product of the two consecutive terms is negative.What is the number of vatiations in sign for the sequence 1,-3,2,5,-4,-6?[    Answer:three ]

连题都看不懂.

2.Malik's recipe for 4 servings of a certain dish requires 1.5 cups of pasta. According to this recipe, what is the number of cups of pasta that malik will use the next time he prepares the dish?

1) The next time he prepares this dish, malik will make half as many servings as he did the last time he prepared the dish.

2)malik used 6 cups of pasta the last time he prepared this dish.

[Answer :C]

I don't understand what is the meaning of first sentence.

xxsc

不好意思。我是新手，刚发现了讨论区，找到答案了，谢谢！

yaoyao99

lovetiky：penScript('viewinfo.asp?id=8408&boardid=22',500,400)">请大家提问的时候务必在标题行注明题目的出处