Exercise 7.7.2 An experiment was conducted to examine thrust forces when drilling under different conditions. Data were collected for four drilling speeds and three feeds.

Speed Feed 100 250 400 550 121 98 83 58 124 108 81 59 0.005 104 87 88 60 124 94 90 66 110 91 86 56 329 291 281 265 331 265 278 265 0.010 324 295 275 269 338 288 276 260 332 297 287 251 640 569 551 487 600 575 552 481 0.015 612 565 570 487 620 573 546 500 623 588 569 497