What number is the best prediction! Please help :(

What is the slope of a line that is perpendicular to y = 3x + 1

How many of the 250 grandparents in the population would you expect to prefer online shopping with merchant a? merchant a: 4 merchant b: 6 merchant c: 2 merchant d: 3 other: 5 none: 5 answer choices: a.about 4 b.about 8 c.about 40 d.about 21

Ab and bc are tangent to circle d. find x is ab = 3x + 8 and bc = 26. find x