None
None
None
replace
replace
最新 is, as you can probably guess, "the newest." So, the newest sharp thing, is the cutting edge. It is state of the art.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
かつて、少し前までは、3Dプリンタは最新鋭の機械でした。
Once, a little while ago, 3D printers were cutting edge machines.
An update is needed before you can continue but you have more than one WaniKani tab open.
Finish up whatever you are doing on the other tab(s), then close them to continue.
The update will complete automatically once the other tab(s) are closed.