राजमिस्त्री के गुनिया (Mason's square) का उपयोग मुख्य रूप से निम्नलिखित में से किस उद्देश्य के लिए किया जाता है?

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?