What are the external hardware devices? Eplain how to connect them and what it use for.

Dean wants a quick way to look up staff members by their staff id. in cell q3, nest the existing vlookup function in an iferror function. if the vlookup function returns an error result, the text “invalid staff id” should be displayed by the formula. (hint: you can test that this formula is working by changing the value in cell q2 to 0, but remember to set the value of cell q2 back to 1036 when the testing is complete.)

Amedian in the road will be marked with a white sign that has a black arrow going to the left of the median. true false

Perform the following tasks: a. create a class named testclass that holds a single private integer field and a public constructor. the only statement in the constructor is one that displays the message “constructing”. write a main()function that instantiates one object of the testclass. save the file as testclass.cpp in the chapter 08 folder. run the program and observe the results. b. write another main()function that instantiates an array of 10 testclass objects. save the file as test class array.c . run this program and observe the results.