I. A sequence where each term after the first is obtained by adding the same constant. II. A sequence where each term after the first is obtained by multiplying the preceding term by the same constant. III. A sequence where its first two terms are either both 1, or 0 and 1; and each term, thereafter, is obtained by adding the two preceding terms.
20. Which of the following statement best describe an arithmetic sequence?
A. I only B. II only C. III only D. none of the above
21. Which of the following statement that best describe the sequence 5, -10, 20, -40, 80 ? A. I only B. II only C. III only D. none of the above
