Determine whether there is any blocking while deleting large number of records

I would like to know whether there is any way to determine why it is taking too much time say 3 minutes for deleting 50K records from a database hosted in Sql Azure. I have clustered index on primary key and a non-clustered index on ID which is being used in where condition in Delete Query

DECLARE @RowsDeleted INTEGER
SET @RowsDeleted = 1

WHILE (@RowsDeleted > 0)
BEGIN
    DELETE top(100) FROM table WHERE ScenarioID= @ID
    SET @RowsDeleted = @@ROWCOUNT
END

Is there any way to know whether there are any locks on this table

indexes:

ALTER TABLE [dbo].[ActCost] ADD  CONSTRAINT [PK_ActCost] PRIMARY KEY CLUSTERED 
(
    [ActCostID] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON)
GO



 Alter NONCLUSTERED INDEX [IX_ActCost_ScenarioID] ON [dbo].[ActCost] ([ScenarioID] ASC)
INCLUDE ( <list_all_other_columns_returned> );
GO


CREATE TABLE [dbo].[ActCost](
    [ActCostID] [int] IDENTITY(1,1) NOT NULL,
    [ActID] [int] NOT NULL,
    [ActCostTypeID] [int] NOT NULL,
    [Description] [nvarchar](200) NOT NULL,
    [Cost] [float] NOT NULL,
    [CostPerProductUnit] [float] NOT NULL,
    [CostPerEndProductUnit] [float] NOT NULL,
    [OtherValue] [float] NULL,
    [OtherID] [int] NULL,
    [Comment1] [nvarchar](200) NULL,
    [Comment2] [nvarchar](200) NULL,
    [OPerProductUnit] [float] NULL,
    [OPerHour] [float] NULL,
    [OCostPerUnit] [float] NULL,
    [OCostPerHour] [float] NULL,
    [PerfEnh_ProcessID] [int] NOT NULL,
    [PerfEnh_MillID] [int] NOT NULL,
    [ScenarioID] [int] NOT NULL,
 CONSTRAINT [PK_ActCost] PRIMARY KEY CLUSTERED 
(
    [ActCostID] ASC
)WITH (PAD_INDEX  = OFF, STATISTICS_NORECOMPUTE  = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS  = ON, ALLOW_PAGE_LOCKS  = ON)
)

GO

Azure Space : Available 2 GB Used :500MB

I have another database with same data but with more Available Size which works fine i mean it takes just 20-30 seconds to do the same job , Is it going to be a factor ?

Blocking inspection :