Macmillan Learning Spider silk is the strongest known material natural or man made on a weight basis A study examined the mechanical properties of spider silk using 21 female golden orb weavers Nephila clavipes The data on silk yield stress represents the amount of force per unit area needed to reach permanent deformation of the silk strand The data are expressed in megapascals MPa 164 0 478 7 251 3 351 7 173 0 362 0 272 4 740 2 329 0 448 9 327 2 270 5 300 6 332 1 288 8 176 1 282 2 236 1 358 2 270 5 290 7 Click to download the data in your preferred format Excel Minitab14 18 Minitab18 JMP SPSS TI R Mac TXT PC TXT CSV CrunchIt Use the software of your choice to make a dotplot of these data Select the correct description of the shape center and spread of the distribution O The distribution is unimodal and extremely left skewed except for a high outlier The center is approximately 240 MPa The spread is from 164 0 to 740 2 MPa The distribution is unimodal and extremely left skewed except for a high outlier The center is approximately 350 MPa The spread is from 164 0 to 478 7 MPa The distribution is unimodal and essentially symmetric except for a high outlier The center is approximately 291 MPa The spread is from 164 0 to 740 2 MPa The distribution is unimodal and essentially symmetric except for a high outlier The center is approximately 291 MPa The spread is from 164 0 to 478 7 MPa