Page Object is a Design Pattern which has become popular in test automation for enhancing test maintenance and reducing code duplication. A page object is an object-oriented class that serves as an interface to a page of your AUT. The tests then use the methods of this page object class whenever they need to interact with the UI of that page. The benefit is that if the UI changes for the page, the tests themselves don’t need to change, only the code within the page object needs to change. Subsequently all changes to support that new UI are located in one place.
You can fill in one or both of these fields. If you fill in both, the MotoWizard will consider only exactly that size propeller. If you fill in only one field, that measurement will be restricted but the other will not. For example, if you select Specific Size and select a diameter of 10 inches but leave the Pitch field blank, the MotoWizard can consider various 10 inch diameter propellers such as 10x5, 10x6, 10x7, and so on (this can be handy when you're trying to choose a propeller that looks right on a scale model). Click the Next button to go to the Battery options page... Battery Options On the Battery options page, you can choose the type of batteries that you want the MotoWizard to consider, or specify exactly the battery you want to use.
In the early 20th century, Bertrand Russell gave a different complete axiomatization of propositional logic, considered on its own, in his 1906 paper "The Theory of Implication", and later, along with A. N. Whitehead, produced another axiomatization using disjunction and negation as primitives in the 1910 work Principia Mathematica . Proof of the possibility of defining all truth functional operators in virtue of a single binary operator was first published by American logician H. M. Sheffer in 1913, though C. S. Peirce (1839-1914) seems have discovered this decades earlier. In 1917, French logician Jean Nicod discovered that an axiomatization for propositional logic using the Sheffer stroke involving only a single axiom schema and single inference rule was possible.