Following the guidelines of your Post#14, I have been able to trace the locations of the library files as follows:
1. Library files that are automatically installed when the IDE (1.8.0) is installed are found here:
a. c:\Program Files\Arduino\libraries\Library folders for 19 devices ike: LiquidCrystal and etc.
b. c:\Program Files\Arduino\hardware\arduino\avr\libraries\Library folders for 5 devices ike: SPI, Wire and etc.
2. Library files that are automatically installed when we download them as zip files, and later on include them using the IDE (Add .ZIP Library...).
c:\Users\GM\Documents\Arduino\libraries\Library folders for custom devices like: LiquidCrystal_I2C and etc.
Now, we see that there are three libraries; when you say standard library (Post#14), which library folder (1a, 1b, or 2) are you referring?
BTW: Enabling verbose does not provide the above information (1a, 1b, and 2).
Many many thanks along with karma point.