Aplumber charges a service call fee of $25 plus $40 for each hour she works. which variable is the independent variable?

a. the total cost of the plumber's services for a service call

b. the number of hours the plumber works on a service call

c. there is no relationship between the variables

What is the absolute value of -100000000000000?

Harold wrote this equation to model the level of water in a pool over time. the variable x represents time in hours. f(x) = 3,500 - 225x which statements about the situation are true? check all that apply. the water level is rising. the water level is falling. the initial level of water in the pool was 3,500 units. the initial level of water in the pool was 225 units. the pool was empty after 14 hours. the water was 2,600 units high after 4 hours.

Graph each quadratic function and identify its key characteristics. f(x) = x^2 - 2x - 3