Its risky...i don't know them particularly well but gonna have another go now. They haven't come up in any of the past exam papers i have done...which may mean they are more likely to come up now! I think they will probably just ask you to show the formation of an oxide (easy, since they are all MO2), then ask whether it is acidic or basic, then ask you to give an equation to illustrate this - ge to pb are all amphoteric oxides.