[phone] Subject Link Karshi-2023 everything grows in spring!

1866 - Celluloid 
In the 19th century, billiards was so popular that a lot of elephants were being killed for their ivory, which 
was used to make billiard balls. So, people tried to find a substitute. A U.S. billiard ball company offered a 
prize of $10,000 to the person who could design the best substitute for natural ivory. In 1866, John Wesley 
Hyatt created Celluloid while trying to win the prize. Although he failed to win, Celluloid was later used to 
make many products, including false teeth, piano keys, and ping pong balls. 
1909 – Bakelite 
Leo Baekeland created Bakelite in 1909. Made entirely of artificial materials, it was the first true plastic.
It was inexpensive, and it kept its shape when heated. Soon, it was being used in many things, including
 
electrical products and jewelry. Since then, many other plastics have been developed. 
Today – Petroleum 
Today, most plastics are produced from non-natural materials made from petroleum. They are light, flexible, 
strong, and cheap. Despite all these advantages, there is one problem: plastic waste breaks down slowly and 
toxic chemicals can leak from it. Therefore, people are trying to develop less harmful plastics. 
 
1. What is the main idea of this passage? 
A) Plastic is harmful to many plants and crops. 
B) New materials are currently being created to replace plastic. 
C) Plastic was originally invented as a substitute for petroleum. 
D) Plastic has been developed and improved over a long period of time. 
 
2. Which item was NOT made with Celluloid? 
A) ping pong balls B) billiard balls 
C) false teeth D) piano keys 
 
3. Which was an advantage of Bakelite? 
A) It broke down very slowly. 
B) It didn’t contain any chemicals. 
C) It could be used to store petroleum. 
D) It could be heated without changing shape.