What is -81=26+n? Please answer if you know

Describe all the numbers that when rounded to the nearest thousand are 645,000

He expression 2(l + w) is used to calculate the perimeter of a rectangle, where l is length and w is width. if the length is fraction 2 over 3 unit and the width is fraction 1 over 3 unit, what is the perimeter of the rectangle in units? fraction 2 over 3 unit 1 unit 1fraction 2 over 3 units 2 units

Can someone pls ! pls answer all. no explanation needed..