Determine the number of significant digits in the measurement of 0.00025 km

The last time i bought this product , it cost $20.00 but it looks like it cost 29. 60 today? what is the increase

Lindsay used two points, (x,y; ) and (+2.82), to find the equation of the line, y = mx + b, that passes through the points. y2-y, first, she used the definition of slope and determined that the value of mis x, - . given this information, which expression must represent the value of b?

Which of the following represents the range of the graph of f(x) below