94.
Consider the following statements and choose the correct answer:
1. In order to increase the photosynthetic efficiency leaf area index should be increased
2. To increase leaf area index plants should be with horizontal leaves
3. If the time of grain-growth is increased, the grain-yield will decrease
4. Photosynthetic efficiency can be increased by monitoring moisture stress, transpiration loss and light intensity

95.
The pressure imposed on a lake-dwelling organism is

96.
If we subject a plant to continuous red light, the level of phytochrome in the plant

97.
Consider the following statements and choose the correct answer:
1. Roots of grasses are an excellent binding material and keep the soil intact
2. Disruption of the grass cover by the plough loosens the soil and makes it vulnerable to removal by the force of rain or strong winds
3. Tilling or grazing on slopes or semi-arid soils decreases the rate of soil erosion
4. Soil erosion is especially high in Nepal, India, China, Australia, Spain, USSR, USA and Central Africa