i wanna ask my case about array and object, i still less of knowledge about this because still newbie. i have bunch of data as following:

```
    counterTraffic : [
    {
      id: 1,
      daerah: "Bandung",
      date:"1668790800000",
      kendaraan: [
        {rodaEmpat: 50},
        {rodaDua: 22},
        {truck: 30},
        {Bus: 70},
      ]
    }, {
      id: 2,
      daerah: "Tasik",
      date:"1668877200000",
      kendaraan: [
        {rodaEmpat: 80},
        {rodaDua: 15},
        {truck: 10},
        {Bus: 50},
      ]
    },
    {
      id: 3,
      daerah: "Bekasi",
      date:"1669050000000",
      kendaraan: [
        {rodaEmpat: 30},
        {rodaDua: 65},
        {truck: 20},
        {Bus: 100},
      ]
    }
    ,
    {
      id: 4,
      daerah: "Bandung",
      date:"1668963600000",
      kendaraan: [
        {rodaEmpat: 20},
        {rodaDua: 15},
        {truck: 5},
        {Bus: 150},
      ]
    }
  ]

```

and i want take value data of counterTraffic.kendaraan and assign to new variable.
so when i go mapping the counterTraffic, and then assign to new variable with kendaraan data

```
the result have to become: let kendaraanNew = [50,22,30,70]

```

the data above from counterTraffic[0].kendaraan that already mapping before.

thank you for your helping