What is the difference between sarcasm and irony?

I'm a principal of a primary nepali school.(class 1 to 5) there are only 3 teachers altogether.it is very difficult to teach them effectively.so one private institute asked me to write an application for 2 teachers with school minutes.i have no idea about it: 1. how to write school minutes and 2. how to write an application for the post of 2 teachers. me kindly.

This passage from chapter 4 of story of my life is an example of which story of plot

"night. no one was praying for the night to pass quickly. the stars were but sparks of the immense conflagration that was consuming us. were this conflagration to be extinguished one day, nothing would be left in the sky but extinct stars and unseeing eyes." explain the images included in the passage. how is the use of the image of night contradictory to how we might expect it to be used