Poly(3-hydroxybutyrate) (PHB), a semicrystalline polymer that is fully biodegradable and biocompatible, is obtained from renewable resources. From a sustain-ability perspective, PHB offers many attractive proper-ties though it is more expensive to produce than standard plastics. The accompanying data on melting point (°C) for each of 12 specimens of the polymer using a differential scanning calorimeter appeared in the article "The Melting Behaviour of Poly(3-1-1ydroxybutyrate) by DSC. Reproducibility Study" (Polymer Testing, 2013: 215-220). 180.5 181.7 180.9 181.6 182.6 181.6

181.3 182.1 182.1 180.3 181.7 180.5

Compute the following:

a. The sample range

b. The sample variance S2 from the definition (Hint: First subtract 180 from each observation.]

c. The sample standard deviation

d. S2 using the shortcut method

(a) 2.3

(b) 0.5245

(c) 0.7242

(d) 0.5245

Step-by-step explanation:

The data provided is:

S = {180.5, 181.7, 180.9, 181.6, 182.6, 181.6,  181.3, 182.1, 182.1, 180.3, 181.7, 180.5}

(a)

The formula to compute the sample range is:

The data set arranged in ascending order is:

S' = {180.3 , 180.5 , 180.5 , 180.9 , 181.3 , 181.6 , 181.6 , 181.7 , 181.7 ,, 182.1 , 182.1 , 182.6}

The minimum value is, 180.3 and the maximum value is, 182.6.

Compute the sample range as follows:

Thus, the sample range is 2.3.

(b)

Compute the sample variance as follows:

Thus, the sample variance is 0.5245.

(c)

Compute the sample standard deviation as follows:

Thus, the sample standard deviation is 0.7242.

(d)

Compute the sample variance using the shortcut method as follows:

Thus, the sample variance is 0.5245.

hello,

b) 62.47% of the students are between 14 and 18 years old.

step-by-step explanation:

mean = 15 and standard deviation = 2

student between 14 to 18

formula used z-score

for age 14 , z score

using z-table , p(z> -0.5)=0.3085

for age 18 , z score

using z-table , p(z< 1.5)=0.9332

p(-0.5< z< 1.5)=0.9332-0.3085 = 0.6247

thus, 62.47% of the students are between 14 and 18 years old.

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step-by-step explanation:

a28=58

step-by-step explanation:

a1=a1+(n-1)d

a28= 4+ (28-1)2

a28=4+(27)(2)

a28=4+54

a28=58