Question

these lights are too cool!
physical science studies: wave interactions
cities around the country
have been using some
new traffic lights. these
lights last longer and use
less energy. so cities save
money. but the bulbs
dont burn hot enough to
melt snow. this can
cause problems for
drivers.
the traffic lights use led
bulbs. these bulbs use
much less energy than
those used in most traffic lights. thats good for the
environment. its also good for cities. since the bulbs use
less energy, they last for seven or more years. other bulbs
need to be changed every 12 to 18 months.
what else is good about led traffic lights? they dont
waste energy by making heat. this is also a problem,
however. why? the lights dont melt snow. wet snow can

Explanation:

• Option A: The text mentions that LED bulbs don't burn hot enough to melt snow, which can cause problems. Logically, if snow isn't melted, cities would need to pay workers to clean it.
• Option B: The text says LED bulbs last seven or more years, but there's no mention of workers cleaning them every seven years.
• Option C: There is no information in the text about LED traffic lights being easier to set up.
• Option D: The text says cities around the country are using new LED traffic lights, not just snowy cities.

Answer:

A. Cities must pay to have workers clean snow from the LED traffic lights.