The accompanying 25 observations on fracture toughness of base plate of 18% nickel maraging steel were reported in the article “Fracture Testing of Weldments” (ASTM Special Publ. No. 381, 1965: 328–356). Suppose a company will agree to purchase this steel for a particular application only if it can be strongly demonstrated from experimental evidence that true average toughness exceeds 75. Assuming that the fracture toughness distribution is symmetric, state and test the appropriate hypotheses at level .05, and compute a P-value.