Idon't get this can someone solve/ me with this appreciate it you

In trapezoid abcd, ac is a diagonal and ∠abc≅∠acd. find ac if the lengths of the bases bc and ad are 12m and 27m respectively.

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?

How many doughnuts are equal to 20 cookies.? 3 apples = 5 bananas6 cookies = 7 apples2 doughnuts = 1 banana