10.) A book that normally cost $5.50 is marked up by 40%. What is the
selling price of the book?

2.2

Step-by-step explanation:

the answer is seven point seven

a complex number is a number that can be expressed in the form a + bi, where a and b are real numbers, and i is a solution of the equation x2 = −1. because no real number satisfies this equation, i is called an imaginary number. has no real solution, since the square of a real number cannot be negative.