Answer:
1) 50 facing towards the right
2) 150 facing right
3) 200 facing right
4) 0- no direction
5) 50- facing left
6) 50 facing right
Explanation:
forces in opposite directions and equal magnitudes counteract each other. in number 2 they face the same direction so they would just be added. in number 4 they oppose each other so would be subtracted
First overtone of open organ pipe is given as

first overtone of closed organ pipe is given as

now they are in unison so we will have




so end correction of both pipes is e = 1 cm