$1.$ This assignment consists of two problems, as described on the following pages.

$2.$ Use Draw.io to draw a conceptual ER model for each of the problems.

i$.$ Go to https:$//$app$.$diagrams.net$/$

ii$.$ Click Create New Diagram

iii. Click $$Edit Data$$ on the lower right corner of the Draw.io screen

iv$.$ Enter the following two properties and assign appropriate values

$$ author: Enter name

$$ email: Enter email address

v$.$ Click $$Apply$$ to go back to the main screen

vi$.$ Adjust the text font size to at least $14$ pt so that the text in the output image is easier to read. To do this, press Ctrl $+$ A to select all entities and relationships in the diagram. The Text tab on the right panel allows you to set the font size.

$3.$ You may make any reasonable assumptions but make sure you clearly list them at the end of your solution. Unstated assumptions will be regarded as modeling errors.

$4.$ You may add any additional attributes that you feel necessary.

$5.$ Once you complete an ER diagram on Draw.io$,$ save it to TWO different files$/$formats: PNG and XML $(.$drawio$).$ To do this, on Draw.io$,$ under the File menu, click Save As$....$ Then you can specify the file name, type, and where to save the file $($see the screenshots below$).$ We need two files$/$formats because you need to $($a$)$ paste the PNG images in the solution area below and $($b$)$ upload the XML $(.$drawio$)$ files. In other words, three files are needed in your final submission:

i$.$ A modified version of this Word document with your solutions in the area below.

ii$.$ assignment$1\_$problem$1.$drawio $($this is the XML file for problem $1)$

iii. assignment$1\_$problem$2.$drawio $($this is the XML file for problem $2)$

Problem $1$:

Delta Airlines owns many airplanes, and each airplane is identified by an ID and characterized by the number of seats and years of service. To maintain these airplanes, Delta Airlines has about $1000$ technicians across all major airports in the US$.$ Each technician has an employee ID$,$ address, SSN$,$ and a list of skills, and is assigned to a specific airport. Maintenance is performed on each airplane regularly or as necessary, and Delta wants to keep detailed maintenance logs of each maintenance activity performed by a specific maintenance team. For each maintenance, Delta tracks the maintenance date, the activity description, and the costs associated with it$.$ At least $3$ or more technicians form a maintenance team for a certain duration. Each team is assigned a unique team ID$,$ and the start date and end date of each team are recorded as well. In general, a type of maintenance activity is performed on an airplane at most once on any day.

Solution to Problem $1($copy$-$paste your PNG image below$)$:

Additional assumptions $($if any$)$:

a$....$

b$....$

Did you also download this ER diagram from Draw.io in XML $(.$drawio$)$ format and name the file as assignment$1\_$problem$1.$drawio? $[$Yes$/$No$]$

$$ Your Answer: $\_\_\_\_\_$

$$ Note: The answer must be Yes because you need to submit this XML file

Problem $2$:

A company is developing a new online platform for job postings and recruitment. The system aims to streamline the process of connecting employers with potential candidates. On this platform, employers are identified by a unique ID$,$ company name, website, and contact details. Employers can create multiple job postings. Each job posting has a number of attributes, such as a unique identifier, title, description, salary, and posting date. Job listings can belong to different categories $($e$.$g$.,$ IT$,$ Marketing, Finance$).$ A job posting may include a set of skills required for the position. On the other hand, applicants can apply to multiple job postings. Each applicant has a unique identifier, name, contact information, and a resume. Applicants possess a set of skills. Applicants may submit multiple applications on the platform, but they cannot apply to the same job posting twice. On the platform, each application is tracked in terms of whether status is pending, accepted, or rejected. As a feature of the platform, it allows applicants to rate their experience with the application process for each of the job postings they applied for.

Solution to Problem $2($copy$-$paste your PNG image below$)$:

Additional assumptions $($if any$)$:

a$....$

b$....$

Did you also download this ER diagram from Draw.io in XML $(.$drawio$)$ format and name the file as assignment$1\_$problem$2.$drawio? $[$Yes$/$No$]$

$$ Your Answer: $\_\_\_\_\_$

Note: The answer must be Yes