It would seem that another application is locking the package manager.

Is Synaptic open?
Are you updating your system or some applications using Update Manager?
Are you installing an application using Software Center?  

If so, wait until these operations are completed, and try to install your application again.

Terminal error File system read only (Solo lectura)
I have to make a reverse engineering. I have two different type of capacitors. What do the Across-The-Line X2 and Line-To-Earth Y2 mean? And what are the differences between them. I searched it but i couldn't find a certain answer.
