Question

Suppose that full time students graduate and start looking for a job. Other things the same, this makes

		both the labor force and the unemployment rate rise
		the labor force will remain the same and the unemployment rate rises
		the labor force will rise while the unemployment rate remains the same
		both the labor force and the unemployment rate remains the same

Answer 1

Both labour force and unemployment rate will increase

These are the full time students who were previously not a part of labour force. Now they have graduated and they are looking for a job which means they are unemployed and also a part of labour force. unemployment increases and at the same time unemployment rate also increases because unemployment rate is the the fraction of labour force which is unemployed. When both unemployment and labour force increase by the same amount, unemployment rate increases.