The range of the following relation R {(3, −5), (1, 2), (−1, −4), (−1, 2)} is Your a{−1, 1, 3} b{−5, −4, 2} c{−1, −1, 1, 3} d{−4, −5, 2, 2}

How many 3-digit numbers can you write using only digits 1 and 7? (of course, digits can repeat.) how many 3-digit numbers can you write using only digits 1 and 7? (of course, digits can repeat.)