4 6 1 2 Call Center Central An important input to staffing decisions at Call Center Contral is the time customer service representatives spend answering calls. Call Center Central's manager monitors call times by selecting, at random, six incoming calls each hour. For each call sampled the manager records the duration of the call (in seconds) The average duration of the calls sampled over the last year is 320 seconds with an average range of 48 seconds for samples of size 6 Sample data for the last seven hours is provided in the table below Call Hour 1 2 3 5 x R 1 297 315 341 354 333 304 324 57 327 346 351 300 337 319 330 51 328 319 314 315 335 315 321 21 339 310 334 354 329 302 328 52 5 349 358 301 312 314 310 57 301 323 340 346 342 310 327 45 339 337 338 325 307 322 328 32 The manager wants to use control charts, along with the sample data above, to assess whether the process was stable over the last seven hours Calculate the CL, UCL and LCL for the R-chart and x-bar chart Enter the valuos in the appropriate fields below. R-Chart 1 UCLI- (Round up to the closest integer) 3 3 4 324 6 7 CLI- Calculate the CL, UCL and LCL for the R-chart and x-bar chart. Enter the values in the appropriate fields below R-Chart Time left 2:20:10 1 UCL (Round up to the closest Integer.) CLI LCLT- (Round down to the closest integer) & chart 1 UCL|-- 1 1 (Round up to closest integer) CL ---- LCL ---- (Round down to closest integer) 1 Was the process stable over the last seven hours? The sample data levidence that an assignable cause was impacting the process