You and your friends plan to prepare dinner following steps will perform 

1.  Time taken to buy the cheese is 30min then make slices of cheese this will take 5min. 

2.  Cut the onion and other vegetables and time taken by this is 7min then 25 min spend to the sauce 

3.  10 min in boil the water after that we put the noodles in water and boil them for 15min,  2min  spend in draining the noodles. 

4.  Assemble all the ingredients and preheat the oven to bake the final dish, will takes 10,  15  and  30  min respectively. Identify the activity and draw a network diagram for this.  Also calculate the maximum time taken to make the dish.