How to decode extrinsic at json-RPC call's data(byte code)

Question

I call json-RPC through the terminal and get the data as below.

extrinsics is raw byte, but I'm using polkadot-js(SCALE codec?) to decode it.

But I don't know which method to call.

"block": {
"extrinsics": [
"0x280402000be1da78d37e01","0xd91f..(too long haha)..580" ],
"header": { "digest": { ... }

@polkadot/crypto-util? @polkadot/util? Which module and which method should I use? I want input string(raw data) and get string(json or human data) please help..