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Will mark brainliest question in the pic.

Ateacher wanted to buy a chair, a bookshelf, two tables and a desk. she spent $900 for all five items and the chair and the desk combined 70% of her total. if the bookshelf cost $50, how much did each of the tables cost?

Sawsan recorded the favorite sport of students at her school. she surveyed 200 students. how many students chose tennis?