Then he turned and left, closing the door behind him. She heard him bolt it, which was totally unnecessary because she had no way of getting free from the bed.

She lay for several minutes looking at the narrow strip of light over the door. Then she moved and tried to feel how tight the straps were. She could pull her knees up a bit, but the harness and the foot restraints grew taut immediately. She relaxed. She lay still, staring at nothing.

She waited. She thought about a gasoline can and a match.

She saw him drenched with gasoline. She could actually feel the box of matches in her hand. She shook it. It rattled. She opened the box and selected a match. She heard him say something, but she shut her ears, did not listen to the words. She saw the expression on his face as she moved the match towards the striking surf ace. She heard the scraping sound of sulphur. It sounded like a drawn-out thunderclap. She saw the match burst into flame.

She smiled a hard smile and steeled herself.

It was her thirteenth birthday.

PART 1. Irregular Equations DECEMBER 16-20

Equations are classified by the highest power (value of the exponent) of their unknowns. If this is one, the equation is of first degree. If this is two, the equation is of second degree, and so on. Equations of higher degree than one yield multiple possible values for their unknown quantities. These values are known as roots.

The first-degree equation (the linear equation):

3x−9 = 0 (root: x = 3)

CHAPTER 1 Thursday, December 16-Friday, December 17

Lisbeth Salander pulled her sunglasses down to the tip of her nose and squinted from beneath the brim of her sun hat. She saw the woman from room 32 come out of the hotel side entrance and walk to one of the green-and-white-striped chaises longues beside the pool. Her gaze was fixed on the ground and her progress seemed unsteady.