In the previous lecture, I said - "When a pod is created the containers are assigned a default CPU request of .5 and memory of 256Mi". For the POD to pick up those defaults you must have first set those as default values for request and limit by creating a LimitRange in that namespace.

    apiVersion: v1
    kind: LimitRange
    metadata:
      name: mem-limit-range
    spec:
      limits:
      - default:
          memory: 512Mi
        defaultRequest:
          memory: 256Mi
        type: Container

https://kubernetes.io/docs/tasks/administer-cluster/manage-resources/memory-default-namespace/

    apiVersion: v1
    kind: LimitRange
    metadata:
      name: cpu-limit-range
    spec:
      limits:
      - default:
          cpu: 1
        defaultRequest:
          cpu: 0.5
        type: Container

https://kubernetes.io/docs/tasks/administer-cluster/manage-resources/cpu-default-namespace/

References:

https://kubernetes.io/docs/tasks/configure-pod-container/assign-memory-resource