Lava is made up of crystals, volcanic glass, and bubbles (volcanic gases). As magma gets closer to the surface and cools, it begins to crystallize minerals like olivine and form bubbles of volcanic gases. When lava erupts it is made up of a slush of crystals, liquid, and bubbles. The liquid freezes to form volcanic glass. Chemically lava is made of the elements silicon, oxygen, aluminum, iron, magnesium, calcium, sodium, potassium, phosphorus, and titanium (plus other elements in very small concentrations. Have a look at the background information in Minerals, Magma, and Volcanic Rocks.
The HoverJack has a weight limit of 1200 lbs. When lifting a heavy patient, extra caution must be taken to center him or her properly on the HoverJack. partners
Jockey being weighed post-race, holding equipment. Jockeys must be light to ride at the weights which are assigned to their mounts. There are horse carrying weight limits, that are set by racing authorities. The Kentucky Derby, for example, has a weight limit of 126 lb (57 kg) including the jockey's equipment.The weight of a jockey usually ranges from 108 to 118 lb (49 to 54 kg). Despite their light weight, they must be able to control a horse that is moving at 40 mph (64 km/h) and weighs 1,200 lb (540 kg).Though there is no height limit for jockeys, they are usually fairly short due to the weight limits.Jockeys typically stand around 4 ft 10 in (1.47 m) to 5 ft 6 in (1.68 m).he weight of a jockey usually ranges from 108 to 118 lb (49 to 54 kg). Despite their light weight, they must be able to control a horse that is moving at 40 mph (64 km/h) and weighs 1,200 lb (540 kg).