It takes 17 full specific type of trees to make one tonne of paper. If there are 221 such trees in a forest, then what fraction of forest will be used to make 5 tonnes of paper.

If a tree falls in the forest where there in no one to hear, does it make a sound ?

Savitri had tc make a model of a cylindrical Kaleidoscope for her science project.She wanted to use chart paper to make the curved surface of the Kaleidoscope.What should be the area of chart paper required by her,if she wanted to make a Kaleidoscope of length 25 cm with a 3.5cm radius?

Noise is a common problem in both urban and rural areas, traffic noise in particular. Trees and shrubs are not only visually attractive but also can make effective noise barriers. Therefore when space permits we have to plant more trees and shrubs in areas where there is noise problem. By doing this noise can be reduced by six decibels over a distance of 30 metres. The only thing we have to keep in mind is that the planting should be particularly dense, the trees which have dense foliage and relatively vertical orientation of arrangements should be planted. It will completely screen the source of noise. If there is any gap in barrier it will still allow noise to penetrate. Single layer of trees is worthless as a noise barrier. Due to inter-reflection, multi-rows of trees are more effective. The planted trees must be taller. We can reduce noise level by 1.5 decibels with each additional 3 feet of tree height When the opportunity to use trees is restricted a combination of shrubs and tall grass can be used. Instead of tarmac or gravel surfaces soft grass ground cover is preferable. It will absorb noise rather than reflect it. Rows of trees, shrubs, crotons, ground covering plants, climbers and their flowers not only reduce noise and provide a beautiful backyard they also help block wind, provide shade, and absorb traffic pollution. Higher the trees

Which among the following are the major reasons behind preferring Eucalyptus tree in the planned forestation process? 1. Plantation grows very fast. 2. Plantation makes the soil more fertile. 3. Wood from Eucalyptus tree is easily converted into pulp for paper industry. Select the correct answer using the code given below :

In the tropical rainforest, the majority of trees have showy animal-pollinated flowers. In temperate forests the majority of trees are wind pollinated. Which factors best explain these contrasting patterns ? (i) Wind is rare in tropical forests. (ii) Because of high species diversity in the tropics, individuals of trees species are often widely separated making wind an inefficient means of pollen dispersal. (iii) More opportunities for coevolved mutualisms exist in tropical forests because of the high diversity of animal species. (iv) Trees in tropical forests are mostly evergreen and year-round leaf canopies impede pollen dispersal by wind. (v) Flowering in tropical forests occurs over a short period of time when wind is absent.