Teaching BPSC बिहार प्राथमिक (1 to 5) शिक्षक भर्ती 4.0 Mock Test General Science Chemistry Periodic Table
What is the purpose of adding gypsum in Portland cement?
1
To lessen the cost of manufacturing
2
To slow down the process of setting.
3
To increase the brightness
4
More than one of the above
5
None of the above