If the approximate energy of a photon present in an x-ray is 8.0 × 10-15 joules, what's the frequency of the x-ray? given: planck's constant is 6.63 × 10-34 joule·seconds.
(a)1.2 × 1014 hertz
(b)1.2 × 1019 hertz
(c)8.2 × 1018 hertz
(d)8.3 × 1019 hertz

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.