Haya would like to completely delete slide 11 from her presentation so that slides 12–16 become slides 11–15. what is one way she can delete slide 11? in normal view, selecting all of the content on the slide by pressing control +a and then pressing delete in normal view, clicking on the slide 11 thumbnail and dragging it down below slide 16 in slide sorter view, selecting slides 12–16 and then dragging them until the insertion point is before slide 11 in slide sorter view, selecting slide 11 and then right-clicking on it and choosing delete slide

The idea that, for each pair of devices v and w, there’s a strict dichotomy between being “in range” or “out of range” is a simplified abstraction. more accurately, there’s a power decay function f (·) that specifies, for a pair of devices at distance δ, the signal strength f(δ) that they’ll be able to achieve on their wireless connection. (we’ll assume that f (δ) decreases with increasing δ.) we might want to build this into our notion of back-up sets as follows: among the k devices in the back-up set of v, there should be at least one that can be reached with very high signal strength, at least one other that can be reached with moderately high signal strength, and so forth. more concretely, we have values p1 ≥ p2 ≥ . . ≥ pk, so that if the back-up set for v consists of devices at distances d1≤d2≤≤dk, thenweshouldhavef(dj)≥pj foreachj. give an algorithm that determines whether it is possible to choose a back-up set for each device subject to this more detailed condition, still requiring that no device should appear in the back-up set of more than b other devices. again, the algorithm should output the back-up sets themselves, provided they can be found.\