If f(x) = x², give the vertex and the three basic points of the graphs of f(x--.75), f(x) - .85, 5 f(x) and 5 f(x--.75) + .85. Quickly sketch each graph.

If water depths of 9.9, -7, -16.1 and -17.4 cm are observed at clock times 34.6, 51.9, 69.2 and 86.5 sec, then at what average rate does the depth change during each time interval?

Sketch a graph of this data set and use a sketch to explain why the slope of this graph between 51.9 and 69.2 sec represents the average rate at which depth changes during this time interval.