Best Summary Selection Practice Test

Recycling is the process of converting waste materials into new materials and objects. It is an important way to manage waste and protect our environment. When we recycle items like paper, plastic, and glass, we reduce the need to extract new raw materials from the Earth, which helps conserve natural resources like trees and minerals. Recycling also saves energy. Making a product from recycled materials almost always requires less energy than making it from new materials. Finally, recycling helps reduce pollution by decreasing the amount of waste sent to landfills and incinerators.

Comets are often called "dirty snowballs" because they are made of ice, dust, and rock. These celestial bodies orbit the Sun in long, oval-shaped paths. When a comet gets close to the Sun, the heat causes some of its ice to turn into gas, creating a glowing cloud around the comet called a coma. The solar wind then pushes this gas and dust away from the comet, forming a long, beautiful tail that always points away from the Sun. While asteroids are also small bodies that orbit the Sun, they are made mostly of rock and metal and do not form tails.