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From 1973 to 1989, total energy use grew less than 10 percent, but electrical energy use grew more than 50 percent. If a part grows much faster than the whole, then that part's share of the whole increases.
Total energy +50%; GNP +>50%.
Find the answer that says electrical energy's share of total energy use grew during the period.
If the statements above are true, then which one of the following must also be true?
Most of the energy used
This claims most energy used in 1989 was electrical. But the stimulus only tells us about percentage changes, not starting levels. Electrical energy could have started as a small fraction of total energy in 1973 and still have grown faster than the total without becoming the majority by 1989. Without baseline data, this conclusion overshoots what the stimulus supports.
2% picked this
From 1973 to 1989 there
Non-electrical energy use does not have to decline — it just has to grow more slowly than electrical use. Total energy grew, electrical energy grew much faster than total, but non-electrical energy could still have grown slightly (just by less than 10%) while still losing share. The stimulus does not require non-electrical energy use to fall.
17% picked this
From 1973 to 1989 there
Why this is right
This must be true. Total energy use grew less than 10%, but electrical energy use grew more than 50%. Whenever a component grows much faster than the whole, that component's share of the whole increases. So the proportion of total energy use that consisted of electrical energy went up between 1973 and 1989.
Skill tested: Must be True · how this choice captures the argument's function is the move to repeat next time.
71% picked this
In 1989 electrical energy constituted
The stimulus does not say anything about how each form of energy is used to produce GNP. We know GNP grew, and electrical energy grew, both at similar rates. But we have no information about how much GNP each form of energy supports. This goes beyond what the stimulus tells us.
6% picked this
In 1973 the electrical energy
This compares electrical energy's share of GNP in 1973 to all other forms combined — a comparison the stimulus does not make. We have no information about the relative size of electrical and non-electrical energy in either year, in absolute terms or as shares of GNP.
4% picked this
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