Alan has read ​10% of a book. He has 81 more pages to finish. How many pages are there in the​ book?

What is the greatest common factor of 6a, 8a^{2}, and 14?

Statement reason 1. δabc is similar to δced. given 2. 3. definition of slope 4. slope of slope of definition of slope 5. slope of × slope of multiplying the slopes 6. slope of × slope of substitution property of equality 7. slope of × slope of simplifying the right side the table contains the proof of the relationship between the slopes of two perpendicular lines. what is the reason for statement 2? a. parallel line segments that meet a common perpendicular line are proportional in length. b. the lengths of vertical and horizontal sides in congruent triangles are in a common ratio. c. trigonometric identities determine the lengths of the legs in a right triangle. d. corresponding side lengths in similar triangles are proportional in length.

Determine whether the question is a statistical question. explain. 1. what is the eye of sixth grade students? 2. at what temperature (in degree fahrenheit) does water freeze? 3. how many pages are in the favorite books of students your age? 4. how many hours do sixth grade students use the internet each week? you!