$10-1.$ A $12-$in$.$ square concrete pile is driven into loose sand to a depth of $30$ ft $.$ Soil conditions are shown in Figure $10-34.$ Find the pile's axial capacity if $K$ is assumed to be $0\mathrm{.}7$ and the factor of safety is $2.$

$10-2.$ Rework Problem $10-1,$ assuming that the groundwater table is located $5$ ft below the ground surface.

$10-8.$ A $12-$in$.-$diameter concrete pile is to be driven into a clay soil as shown in Figure $10-38.$ The pile's design capacity is $30$ tons. Determine the pile's required length if the factor of safety is $2.$

FIGURE $10-38$

rsity of New York

$11-4.$ What is the total active earth pressure per foot of wall for the wall shown in Figure $11-39,$ using Rankine theory?

$11-7.$ What is the total active earth pressure per foot of wall for the retaining wall in Problem $11-4,$ with an angle of wall friction between backfill and wall of $25,$ using Coulomb theory?