1. The problem asks to write the given numerals in words. 2. Writing numbers in words involves naming each digit group according to its place value (units, thousands, millions, etc.). 3. Let's write each number in words: (a) 13 457: "thirteen thousand four hundred fifty-seven" (b) 258 674: "two hundred fifty-eight thousand six hundred seventy-four" (c) 3 918 243: "three million nine hundred eighteen thousand two hundred forty-three" (d) 75 243 968: "seventy-five million two hundred forty-three thousand nine hundred sixty-eight" (e) 5 613: "five thousand six hundred thirteen" (f) 43 286 714: "forty-three million two hundred eighty-six thousand seven hundred fourteen" Each number is broken down into groups of three digits from right to left, and each group is named accordingly.