Suppose the cache access time is 10ns, main memory access time is 200ns, and the cache hit rate is 80%. Assuming parallel (overlapped) access (or say, load-through is used), what is the average access time for the processor to access an item

In many applications, only a small percentage of the points in a given set p of n points are extreme. in such a case, the convex hull of p has less than n vertices. this can actually make our algorithm convexhull run faster than θ(nlogn). assume, for instance, that the expected number of extreme points in a random sample of p of size r is o(rα ), for some constant α < 1. (this is true when the set p has been created by picking points uniformly at random in a ball.) prove that under this condition, the running time of the algorithm is o(n).