SELECT tblTest.idComm,
Sum(IIf([tblTest]![NumTrim]=1,[tblTest]![CA],Null)) AS T1,
Sum(IIf([tblTest]![NumTrim]=2,[tblTest]![CA],Null)) AS T2,
Sum(IIf([tblTest]![NumTrim]=3,[tblTest]![CA],Null)) AS...