The answer is 130 degrees b
According to Sturge's rule, number of classes or bins recommended to construct a frequency distribution is k ≈ 7
Sturge's Rule: There are no hard and fast guidelines for the size of a class interval or bin when building a frequency distribution table. However, Sturge's rule offers advice on how many intervals one can make if one is genuinely unable to choose a class width. Sturge's rule advises that the class interval number be for a set of n observations.
Given,
n = 66
We know that,
According to Sturge's rule, the optimal number of class intervals can be determined by using the equation:

Here, n is equal to 66 and by substituting the value to the equation we get:

k = 7.0444
k ≈ 7
Learn more about Sturge's rule here: brainly.com/question/28184369
#SPJ4
Answer:
$960
Step-by-step explanation:
1/5= .2
1-0.2= 0.8
1200×0.8= 960
2x-y=1 is also equal to y=2x-1 so then plug in 1 or x and so on to create a table