20. Seventy is 60% of what number?

Find the domain of the following expression: 1/(√x)-2

Afrequency table of grades has five classes (a, b, c, d, f) with frequencies of 3, 13, 14, 5, and 3 respectively. using percentages, what are the relative frequencies of the five classes?

Let x = a + bi and y = c + di and z = f + gi. which statements are true?