Help needed thanks it greatly appretiated

In a graph with several intervals o data how does a constant interval appear? what type of scenario produces a constant interval?

Which of the following quartic functions has x = –1 and x = –2 as its only two real zeroes?

How many 3-digit numbers can you write using only digits 1 and 7? (of course, digits can repeat.) how many 3-digit numbers can you write using only digits 1 and 7? (of course, digits can repeat.)