Explanation:

Only 2

Tughlaqs generally used red sandstone in their buildings: This statement is not correct. The Tughlaq dynasty, known for its architectural contributions, often used a variety of materials in its buildings, including grey quartzite and rubble masonry. The use of red sandstone is more commonly associated with the Mughal architecture that came later.

Firuz Shah Tughlaq used the lotus as a decorative design in all his buildings: This statement is correct. Firuz Shah Tughlaq, who ruled during the Tughlaq dynasty, was known for incorporating the lotus motif as a decorative design in many of his buildings.