Q: Which among the following are essential constituents of Portland cement ?
(a)Sand, lime, clay
(b)Silica, alumina, lime
(c)Silica, lime, graphite powder
(d)Sand, graphene, clay
Correct Answer: (b)
The correct answer is (b): Silica, alumina, lime. Subject: Science & Technology | Sub-topic: Materials & Nanotech