A. Lignite
B. Semi-anthracite
C. Sub-bituminous
D. Bituminous
Correct Answer: Semi-anthracite ✔
Last Updated: March 08, 2019
A. Lignite
B. Semi-anthracite
C. Sub-bituminous
D. Bituminous
Correct Answer: Semi-anthracite ✔
Last Updated: March 08, 2019