What is the value of n so that the expression x^2+11x+n is a perfect square trinomial?

Can any one me with the answers to these questions asap?

Glenda makes an online purchase for picture frames for $12.95 each and formats of $5.89 each the site says it taxes paid by the customer or 6.5% of the total purchase price shipping charges are based on the

Peter measures the angles in a triangle. he finds that the angles are 95, 10 and 75. is he correct? explain your answer