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Hi, I am deaf student. Would you like to help answer my question? I could not know how to solve this question about calculated. So here are the question here: 1. Write a query to show the Emp Full Name, DateJoined, DateLeft and Days Worked. Day Worked will be calculated using the DateLeft and DateJoined. 2. All tasks have to be completed within 50 days after it was given (Date Given). Write a query to show the Task Id, Task Name, Date Given, Due Date, End Date. Due Date will be calculated using the Date Given + 50. 3. Write a query to show the Task Id, Task Name, Start Date, End Date and Num Days. Num Days will be calculated using the Start Date and End Date. my script: -- Spooling Prompts: CR_employee Table PROMPT Creating CR_employee Table create table CR_employee ( EmpId char(2), FirstName varchar(20) NOT NULL, LastName varchar(20) NOT NULL, Gender char(1) NOT NULL CHECK(gender IN ('M', 'F')), DateJoined date NOT NULL, DateLeft date, DayWorked number, Contract char(4) NOT NULL, Constraint CR_employeePK PRIMARY KEY (EmpId) ); -- Spooling Prompts: CR_task Table PROMPT Creating CR_task Table create table CR_task ( TaskId char(4), TaskName varchar(25) NOT NULL, DateGiven date NOT NULL, StartDate date, EndDate date, DueDate date, NumDays number, MaxHours number(3,1) DEFAULT (20.0), Constraint CR_taskPK PRIMARY KEY (TaskId) ); Please give them a comment for answer thanks... I am very sorry for my bad English. Can you understand this ? Please help me to be the last answer before I will submit due on Friday...