**(a)** Write a function that takes as input a model object (variable) fit via `lm()` and outputs a fitted versus residuals plot. Also, create arguments `pointcol` and `linecol`, which control the point and line colors, respectively. Code the plot to add a horizontal line at $y = 0$, and label the $x$-axis "Fitted" and the $y$-axis "Residuals". alok

Suppose a cpu with a write-through, write-allocate cache achieves a cpi of 2. what are the read and write bandwidths (measured by bytes per cycle) between ram and the cache? (assume each miss generates a request for one block.)

Anewly established internet company with 40 employees needs your advice. they are looking for a collaboration tool and have narrowed their choices to gotomeeting, webex, and my web conferences. after reading the information presented in this chapter and other sources, prepare a two- page document ( double spaced) that includes two advantages and two disadvantages of each tool. which one is your final recommendation? why did you choose that tool over the other two?

1. define independent-set as the problem that takes a graph g and an integer k and asks whether g contains an independent set of vertices of size k. that is, g contains a set i of vertices of size k such that, for any v and w in i, there is no edge (v,w) in g. show that independent-set is np-complete.