What are the disadvantages of ramp development method?( )
A: Large amount of development work
B: Trackless equipment has large initial investment, heavy maintenance workload and high technical level requirements
C: The development depth is restricted by driving technology and economic factors
D: No steel is required
A: Large amount of development work
B: Trackless equipment has large initial investment, heavy maintenance workload and high technical level requirements
C: The development depth is restricted by driving technology and economic factors
D: No steel is required
举一反三
- What technolgies forced the development of multimedia technology? A: Storage technology B: Compression technology C: Network technolgy D: Large Scale Integrate Circuit
- What are the technical factors to be considered in mining methods? ( ) A: Equipment level B: Technology method C: Strata control D: Cost per ton of coal
- The western part of China has enormous ( ) for economic development, but a lot of investment is also needed.
- According to the level of economic development, China is a country.
- New technology has enabled development of an online “virtuallibrary”. A: virtual B: economic C: electric D: electrical