1. When was the first airplane flight across Chicago?

a. 1906 b. 1910

c. 1915 d. 1921

2. When did the first electric trolley car begin operating in Chicago?

a. 1890 b. 1902

c. 1920 d. 1912

3. When did the first gas lights appear in Chicago?

a. 1850 b. 1855

c. 1839 d. 1900

4. When was the first playground in Chicago built?

a. 1875 b. 1910

c. 1893 d. 1925