title: ERROR: Constructing component 'objective' from data=None failed: TypeError: 'float' object is not subscriptable
body: <p>Team Pyomo,
  I kindly need help with the above-stated error. I have done everything I could, but still can't get my model to work. Below is the formulation of my 'Objective Function', and screenshots of the errors message. Thank you.</p>
  <p><a href="https://i.stack.imgur.com/QA8I0.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/QA8I0.png" alt="enter image description here" /></a></p>
  <p>Screenshot of the error from the running code at the command prompt:
  <a href="https://i.stack.imgur.com/8NTxd.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/8NTxd.png" alt="enter image description here" /></a></p>