Reading Standards for Informational Text > Complex Characters and Their Journeys (CCSS.RI.6.10) Practice Test

In many cities, summer heat lingers long after sunset. Sidewalks and rooftops soak up sunlight during the day and release it slowly at night, a pattern scientists call the urban heat island effect. Materials like asphalt and dark shingles have a low albedo, meaning they absorb more light than they reflect. That makes neighborhoods without shade feel like ovens during heat waves. The consequences are not just uncomfortable; extreme heat sends people to the hospital and strains the power grid.

The good news is that simple changes can mitigate, or reduce, this heat. Planting street trees spreads a leafy canopy that blocks sunlight and cools the air through evaporation. Painting or replacing dark roofs with reflective coatings bounces sunlight back into the sky. One school district tested a white coating on an old gym roof and measured cooler indoor temperatures without turning up the air-conditioning. Cities that combine shade and reflection make sidewalks more walkable and apartments less stifling. While no single solution can cancel a heat wave, a network of small changes can make the hottest days safer for everyone.

Before telephones carried voices across continents, the fastest way to send a message from Missouri to California was the Pony Express. Starting in 1860, young riders dashed between relay stations, changing horses every dozen miles to keep up a breathless pace. They carried a lightweight mail pouch and a heavy responsibility. Blizzards, swollen rivers, and the threat of attack turned each trip into a test of nerve. Admirers later told stories that made the riders seem almost superhuman.

Yet this bold experiment lasted only about eighteen months. In 1861, the transcontinental telegraph linked the East and West with electric signals that flew over wires in moments. Compared with a galloping horse, the telegraph was faster, cheaper, and less risky. The company running the Pony Express shut down soon after, leaving its legend larger than its lifespan. The service remains a symbol of daring, but it is also a reminder that technology can swiftly replace even the most dramatic human effort.