A:
Lenovo does not consider memory a user upgradable option on this model, because it requires a partial disassembly of the computer to access the module.
By default it comes with a 4GB DDR3L SODIMM which can be swapped for an 8GB, but it would have to be done by someone familiar with working on laptop internals.
Note that if the tech is not Lenovo certified, and doesn't use an OEM Lenovo memory module, it will likely void your warranty.
Aloha, TRP (Lenovo partner service tech)