Lanthanoid which is radioactive is

Which of the following Lanthanoid is radioactive

In the separation of lanthanoids by using cation exchange column, the lanthanoid ion which is obtained first:

Name one lanthanoid element which has radioactive nature.

Which of the following lanthanoids is rediocative ?

TO which group Lanthanoids and actinides belongs ?

Which of the following lanthanoid ions is diamagnetic ?