Heat is supplied to a mono atomic gas at constant pressure . The ratio of $\;\bigtriangleup u : \bigtriangleup W : \bigtriangleup Q\;$ is -

Question

$(a)\;7 : 5 :2\qquad(b)\; 7 : 2 :5\qquad(c)\;3 : 5 : 2\qquad(d)\;3 : 2 :5$