A1 x 2-in. bar is 20 in. long and made of aluminum having sy-25 ksi. with a safety factor of 4, what axial compressive load can be applied if (a) both ends are hinged? (b) one end is built in and the other is unsupported?

A5 foot by 5 foot box culvert is buried 6 feet beneath the surface of the ground. a crosssection of this very long culvert (into and out of the page) is illustrated below. assume that the soil in which the culvert is buried has the following properties: jt = 120 pcf, w = 12%, ko = 0.50, ka = 0.33, and kp = 3.00. calculate the total horizontal force per unit length of culvert (fh) felt on one of the vertical faces of the culvert.