Help! ASAP, this is due tomorrow and I’m struggling as this isn’t what they taught us. The question is: Explain why the bacteria shown (E. coli) have a second membrane outside the peptidoglycan.

Membrane vesicles containing an internal sodium chloride (nacl) concentration of 0.14 m are placed into separate beakers each containing a different solution. the first beaker contains 0.14 m sucrose, while the second beaker contains 0.14 m calcium chloride (cacl2). the temperature is 25°c. what is the solute potential inside the vesicles, expressed in units of mpa?