A(n) _____ card performs hardware diagnostics and displays the results as a series of codes on an LED display or LED light(s)

A(n) ________ bar is useful to quickly identify higher and lower numbers within a large group of data

Fill in the blank(s) with correct word

What special value are the elements of an array of reference type objects equal to by default?

a. 0 b. void c. ?1 d. null