Pick up the correct statement from the following:

• The percentage of absorption for firebricks varies from 5 to 10
• The percentage of silica in silica bricks is to the extent of about 95 to 97 percent
• Roughly 1 to 2 percent of lime in silica bricks is added to act as binding material
• The compressive strength of silica bricks is about 150 kg/cm2
• All the above.