(a) Give one function of each of the following bacteria in Nitrogen cycle:

      ii Rhizobium

      ii Nitrosomonas

      iii Pseudomonas

      iv Nitrobacter

 (b)  A farmer discovered that aphids have invaded a cowpea farm.

  (ii)  State three effects of aphids on the cowpea plants.

 c(i)  Explain the term forestry.

  (ii)  Name five products that could be obtained from forests.