4 .P and Q can complete a piece of work in 14 days and 16 days respectively. P begins to do the work and they work alternately one at a time for one day each. The whole work will be completed in–
A.14$7\over15$ days
B.7$7\over15$ days
C.14$7\over8$ days
D.7$7\over8$ days
5 .In a barrack of soldiers there was stock for 55 days for 300 soldiers. After 31 days 100 soldiers left the barrack. For how many days shall the leftover food last for the remaining soldiers?