Mosquitto_pub the connection was lost mosquitto. conf

Can someone work out the answer as it comes up in one of my computer science exams and i don't understand the cryptovariables

Which type of excel chart should be used to track students’ progress on test grades? line column bar pie

You work in the accounting department and have been using a network drive to post excel workbook files to your file server as you complete them. when you attempt to save a workbook file to the drive, you see the error message: “you do not have access to the folder ‘j: \’. see your administrator for access to this folder.” what should you do first