Help please due today

Two sides of a triangle mesure 20cm and 30cm. what is the measure of the third side

The floor plan of a room has a scale of 2.5 in.: 35 ft. in the drawing, the length of the room is 8 in. and the width of the room is 6 in. what is the perimeter of the actual room?

Fanny mendelssohn manages all the magazines and paperback books at a local grocery store. she prices many paperbacks to sell at $7.99. the cost to the store is $5.29. what is the markup rate on a paperback book, based on its cost?