Help me with pre algebra 50 points

For one history test, keith had to answer 40 questions. of these 40 questions, keith answered 28 of them correctly. what percent did keith get on his history test? round your answer to the nearest tenth if necessary

Tcan be concluded that % of the seniors would prefer to see more candid pictures in this year's edition of the yearbook.

Solve x+3y=6 and 4x-6y=6 by elimination . show work !