What type of motor oil do I put in an 1.6 Meriva Vauxhall Cavalier LIFE?

would like some help in finding the right type of brand for a 1.6 Engine for the Vauxhall Cavalier Life, any, is it synethic or the 10/40 one?|||it will tell you on your cars dash near the oil presser Gage|||Haven't you got, at least a handbook ? A phone call to your local Vauxhall dealer should help.