Question

read the passage. there are several questions about this passage. hoof - style, to its jaw. can you possibly imagine a billion cars? 2 the interesting thing for me isnt that there are so many cars in the world, but why. what is it about cars thats made them, in the space of just over a century, one of the most successful inventions of all time? not surprisingly, the answer is all to do with science. whats so good about cars? 3 cars are chemistry labs on wheels. and though that might not sound so interesting, it accounts absolutely for their ubiquity. take away the leather seats, the gleaming chrome, the go - faster stripes and all the rest, and youre left with a handful of tin cans called cylinders, where petrol explodes into power. cars are built around engines, and engines (or internal combustion engines, to give them their full name) burn petrol with oxygen in the air to release the energy locked inside it. we think of burning as a way of making fire, but its essentially a chemical reaction between oxygen and fuel that just happens to produce heat and fire as a by - product. the simple science of cars is so utterly mundane that we scarcely give it a thought: pump the petrol in your tank, turn the key and off you go. think about it more closely, however, and youll see how astonishing it really is. 4 suppose a typical modern family car does about 40 miles to the gallon or, in metric terms, 100 km for every 7 litres of fuel. that means if you have a teaspoon of petrol (about 0.004 litres), it contains enough energy to roll your car about 60 m (200 ft), or roughly 15 times the cars own length. consider how hard it is to push a car, even once youve got it going from a standstill, and im sure youll agree thats quite remarkable. the simple fact is that petrol is energy locked inside it. (paragraph 3) what does the word it refer to in this sentence? 1. the engine 2. the petrol 3. the oxygen 4. the air part b which detail from paragraph 3 best supports the correct answer from part a? 1. \explodes into power\ 2. \burning as a way of making fire\ 3. \a chemical reaction\ 4. \just happens to produce heat\

Explanation:

In the sentence "engines (or internal combustion engines, to give them their full name) burn petrol with oxygen in the air to release the energy locked inside it", the context is about engines burning petrol to release energy. The "it" clearly refers to the petrol as the energy is locked within the petrol. For Part B, "explodes into power" best supports that petrol is what has the energy locked inside as it describes the result of petrol's combustion - releasing power.

Answer:

Part A: 2. the petrol
Part B: 1. "explodes into power"