Find the domain and range of these functions. (a) the function that assigns to each pair of nonnegative integers the first integer of the pair. (b) the function that assigns to each nonnegative integer its largest decimal digit. (c) the function that assigns to a bit string the number of ones minus the number of zeroes in the string. (d) the function that assigns to each nonnegative integer the largest integer not exceeding the square root of the integer. (e) the function that assigns to a bit string the longest string of ones in the string.