What are the answers to the last 2 questions? Help would be highly appreciated:)

Me. i need an answer asap. , you! select the correct answer from each drop-down menu.simplify the given polynomial and use it to complete the statement.the polynomial simplifies to an expression that is a blank with a blank degree of blank .

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?

In the equation sqrt(n+5)-sqrt(11-10)=1. what is the value of n