किसी भी अच्छी सीढ़ी (staircase) में, अधिकतम और न्यूनतम पिच (झुकाव) किसके बीच होनी चाहिए?

Which of the following statements conform(s) to panel walls in building construction? 1. Panel walls are external load bearing walls. 2. They are self supporting walls subjected to lateral loads. 3. They are primarily used in framed structures.

Which of the following statements conforms to 'corbels' in masonry?