Very short pulses of high-intensity laser beams are used to repair detached portions of the retina of the eye. the brief pulses of energy absorbed by the retina weld the detached portion back into place. in one such procedure, a laser beam has a wavelength of 810 nm and delivers 275 mw of power spread over a circular spot 108 μm in diameter. the vitreous humor (the transparent fluid that fills most of the eye) has an index of refraction of 1.34.

Classify the following soils according to the uscs classification system. provide appropriate uscs designations. a) this sample of well-graded gravel with sand was obtained from a large earthen dam in vancouver, canada. the sample has 73% fine to coarse sub-angular gravel, 25% fine to coarse sub-angular sand and 2% fines. the maximum size of the particles is 75 mm. the coefficient of curvature is 2.7, while the uniformity coefficient is 12.4. b) this dark brown and wet soil with a “strong organic odor” has 100% passing the no. 200 sieve. the liquid limit of the material is 32% when not dried and is 21% when oven-dried. the plastic index is 21% when not dried. c) this sand has 61% predominantly fine sand, 23% silty fines, and 16% fine sub-rounded gravel size. the maximum size is 20 mm. the liquid limit is 33% and the plastic limit is 27%. d) this soil has 74% fine to coarse sub-angular reddish sand and 26% organic and silty dark brown fines. the liquid limit is 37% when not dried and is 26% when oven dried. the plastic index is 6% when not dried.

It can take some of those large , industrial vehicles up to feet to stop when traveling only 60 mph, and therefore , you shoukd be mindful to not be jn the traffic right in front of them a. 100 feet b. 200 feet c. 335 feet d. 425 feet

While standing outdoors one evening, you are exposed to the following four types of electromagnetic radiation: yellow light from a sodium street lamp, radio waves from an am radio station, radio waves from an fm radio station, and microwaves from an antenna of a communications system. rank these type of waves in terms of increasing photon energy.