Change the following sentences from active to passive. Be sure to keep the same tense with each change

10 few students attftended the course
11 the play disappointed us very much
12 Mrs hacker manages the export division
13 jack paid me the money
14 the little boy ate two loaves of bread
15 Janet bought the picture book in kerry's
16 the teacher corrects our exercise at home
17 the boys started a dancing class last week
18 George met Mary at the dance
19 he left the letter on the desk 
20 everyone will see the Picasso exhibition soon