Write the harmful effects done by smog specially in winter

Which of there factors contributed most to us westward expansion in the second half of the nineteenth century?

5. there were nearly 1,000 pirate attacks between 1994 and 2005 off the coast of according to the international maritime bureau's annual piracy report for 2005.

Which of the layers of the earth has the following three characteristics? i. it is a solid outer layer. ii. it is between 3 and 30 miles thick. iii. it is separated into plates. a. the outer core b. the inner core c. the mantle d. the crust