Marking brainliest !! :D enter a range of values for x:

12
d
35
20
b
4 x 4 - 4
c
[?]

∠1 and ∠2 are complementary. ∠1=x°∠2=(3x+30)° select from the drop down menu to correctly answer the question. what is the value of x? . a.15 b.25 c.30 d.40 e.55

()1. how do you find range? 2.the following set of data is to be organized into a histogram. if there are to be five intervals on the graph, what should the length of each interval be? 30, 34, 23, 21, 27, 25, 29, 29, 25, 23, 32, 31

Is experimental probibilty the same as the observed frequency in math? i need the answer asap!