ответить на вопросы ambient divers, unlike divers who go underwater in submersible vehicles or pressure resistant suits, are exposed to the pressure and temperature of the surrounding (ambient) water. of all types of diving, the oldest and simplest is free diving. free divers may use no equipment at all, but most use a face mask, foot fins, and a snorkel. under the surface, free divers must hold their breath. most free divers can only descend 30 to 40 feet, but some skilled divers can go as deep as 100 feet. scuba diving provides greater range than free diving. the word scuba stands for self-contained underwater breathing apparatus. scuba divers swear metal tanks with compressed air or other breathing gases. when using ,open-circuit equipment, a scuba diver simply breathes air from the tank i through a hose and releases the exhaled air into the water. a closed-circuit breathing device, also called a rebreather, filters out carbon dioxide and other harmful gases and automatically adds oxygen. this enables the diver to breathe the same air over and over. in surface-supplied diving, divers wear helmets and waterproof canvas suits. today, sophisticated plastic helmets have replaced the heavy copper helmets used in the past. these divers get their air from a hose connected to compressors on a boat. surface-supplied divers can go deeper than any other type of ambient diver. statements 1. the passage mainly discusses: a) going underwater in submersible vehicles; b) free diving; c) surface-supplied diving; d) various types of diving.2. the passage implies that the oldest type of diving is called: a) ambient diving; b) scuba diving; c) free diving; d) pearl diving. 3. it may be inferred from the passage that all divers: a) use no equipment at all; b) use sophisticated equipment; c) submerge; d) surface. 4. according to the text most free divers use: a) a snorkel, a face mask and hand fins; b) a face mask, foot fins, and a snorkel; c) a self-contained underwater breathing apparatus; d) a snorkel, back fins and helmet. 5. the word "ambient" in line one may most probably mean the following: a) underwater; b) encompassing; c) resistant; d) submersible. 6. one can make a conclusion that most free divers can reach the depth of: a) 10 yards; b) 20 yards; c) 30 yards; d) 40 yards. 7. while going underwater a scuba diver wears: a) a canvas hose; b) a plastic helmet; c) rebreathers; " d) metal tanks. 8. it can be seen from the passage that the rebreather filters out: a) carbon dioxide; b) detrimental gases; c) inert gases; d) open-circuit gases. 9. the passage states that the diver can breathe: a) the same air over and over; b) raw oxygen; c) carbon dioxide; d) other harmful gases. 10. the passage implies that in surface-supplied diving, divers wear: a) intricate canvas helmets; b) sophisticated copper helmets; c) sophisticated plastic helmets; d) heavy copper helmets.
