5 The depth to which a steel pipe pile (deep foundation) can be driven without hitting the rock stratum is denoted as H (see figure). For the new Marine Biology building site at UC Santa Cruz, this depth has a log-normal distribution with a mean (u) of 30 ft and standard deviation (o) of 6 ft. To provide the required foundation support, piles must be embedded 1 ft into the rock stratum. rGround Surface Pile H (a) Rock f(h) Lognormal μ = 30 8 = 20% h, depth in ft (b) a. What is the probability that a pile of length 40 ft will not meet anchor criterion? b. A 40 ft long pile has been driven 39 ft into the ground and no rock has been encountered yet. What is the probability that an additional 5 ft of pile welded to this pile will meet the anchorage requirement? (Conditional