Concerning the 1D d (x) function:
1) what is its value with x not equal to 0?
2) what is its value at x=0 ? (digital and analog domains)
3)what is its frequency content?
4) The 1D rect function has a width of 1; i.e. has a non-zero value between +1/2 and -1/2. What is the width of the delta function?
5) What is the area of the delta function?