title: ER diagram for lab
body: <p>Draw an ER diagram for the following situation: a lab has several chemists who work 
  on one or more projects. Chemists also may use certain kinds of equipments on each 
  project. 
  o Attributes of Chemist include EmployeeID (identifier), Name, and PhoneNo.
  o Attributes of Project include ProjectID (identifier), and StartDate.
  o Attributes of Equipment include SerialNo (identifier) and Cost.
  o The organization wishes to record AssignDate, the date when a given equipment item 
  was assigned to a particular chemist working on a specified project.
  o The organization also wishes to record the association between the project and chemist. A chemist must be assigned to at least one project. Any number of chemists may 
  work in a project.
  o A given equipment item need not be assigned, and a given project need not be assigned any equipment item.</p>
  
  <p><img src="https://i.stack.imgur.com/R72pk.png" alt="sol"></p>
  
  <p>My ans differ slightly from answer key.I dont understand why equip is branched out from assignment.According to the question," A given equipment item need not be assigned, and a given project need not be assigned any equipment item",shouldn't equip be branching out from prject?</p>