Write a function named “createPurchaseOrder” that accepts the quantity (integer), the cost per item(double), and the description(string). It will return a newly created PurchaseOrderobject holding that information if they are valid: quantity and cost per item cannot be negative and the description can not be empty or blank(s). When it is invalid, it will return NULL to indicate that it cannot create such PurchaseOrderobject.

In mathematics and computer science, a set is a collection in which order does not matter and there are no duplicates. in this problem, we are going to to define a class which wil allow us to create an object to represent a set of integers. you will write a program set. java to define the class set. each instance of the class set will be an object representing a set of integers.

To become an audio technician, the most successful tactics might include the following. (select all that apply). learning how to persuade other people gaining different types of experience in audio technology learning as much as possible about art history establishing a reputation as a reliable professional

Scientists have changed the model of the atom as they have gathered new evidence. one of the atomic models is shown below. what experimental evidence led to the development of this atomic model from the one before it? a few of the positive particles aimed at a gold foil seemed to bounce back. the colors of light emitted from heated atoms had very specific energies. experiments with water vapor showed that elements combine in specific proportions. cathode rays were bent in the same way whenever a magnet was brought near them.