1. It cost a fortune. 2. It cost an arm and a leg. 3. That's a rip-off. (= overpriced; far more expensive than it should be) 4. I can't afford it. (= I don't have enough money to buy it) 5. That's a bit pricey. 6. That's quite reasonable. (= it's a good price) 7. It's 20% off. (= there's a 20% discount) 8. That's a good deal. (= a good value for the amount of money) 9. It was a real bargain. 10. It was dirt cheap. (= extremely inexpensive) More Travel English: http://www.espressoenglish.net/travel-english-conversations-in-the-airport
As CNG is stored at high pressure, it is often perceived that the high pressure of the product makes it more hazardous than other fuels. While a high pressure gas leak tends to make a lot of noise while the gas is escaping, the high pressure forces the gas to escape very rapidly causing high concentrations of gas to build up in the immediate vicinity of the leak. The resulting high concentrations of gas and its tendency to dissipate upwards make it less likely for the gas in the immediate vicinity of the leak to ignite. Naturally, the high pressure does cause the gas to escape with some force so obvious precautions are necessary.