Right Angles and Pythagorean Theorem
Geometry, and more...

 1 MEDIUM Which is a pythagorean triple? 5, 12, 133, 5, 712, 13, 213, 7, 12None of the above

 2 HARD A shore of length 25m stretches along the harbor. A dock of length 73m lays perpendicular to the shore at its midpoint. What is the distance from one end of the shore to the tip of the dock? 77.1673.5102.787.130

 3 HARD A pole that is 25m long leans along a brick wall. The pole's lower end is 7m from the base of the wall. Due to a blowing wind, the pole slides 4m down the wall. From its new position, how far is it from the base of the wall to the pole's lower end? 7m11m24m20m15m

 4 HARD Alex wants to climb up on his roof to rescue his cat. To do this, he needs to buy a ladder. Alex's house is 8 metres tall. In order for him to be able to safely climb the ladder, he has to place it so that distance from the base of the ladder to the wall is 60% of the length of the ladder. If ladders cost \$3 per metre of length, how much money does Alex have to spend on a ladder?