i mac 21inch 4k screen

[holty]

is it true if you buy a new machine as above you have to pick your ram at purchase as you cannot upgrade later ??

also how long does it take to charge the wireless mouse and keyboard

 

[andyred]

is it true if you buy a new machine as above you have to pick your ram at purchase as you cannot upgrade later ??

also how long does it take to charge the wireless mouse and keyboard

For the 21" yes, you can still (presently) upgrade the 27" memory yourself...

 

[Andy Taylor]

RAM is now soldered to the logic board of all current Macs apart from the Pro and 27" iMac.

The keyboard and mouse are meant to take 2 or 3 minutes to charge for up to 9 hours use, a couple of hours for about a month of usage.