Task 1: Child Routes

  routes = [
      { path:'account/:accountNo', component: AccountComponent,
        children:[
            {path:'', component:ViewAccountComponent},
            {path:'transactions', component:ViewTransactionsComponent}
        ]
      }
  ]

Task 2: Get Parent Route Params

  accountNo:number;
  this.router.parent.params.subcribe(params=>{
      this.accountNo = params["accountNo"];
  });