my inter view to my secondary resource

Today I interviewed Ibu. Sofia. she is the school general affair manager. the interview is to check how much does the school spend for buying fertilizer and what kind fertilizer that the school use. the answer will be compared to my cost of the compost materials. but the solution is we can't compare it because the school bought for one package for about six months. and if mine the cost is 25,000. but that doesn't include the all the material because I alredy have some of them so this price is only the one that I bought. the school use the pupuk kandang fertilizer. then Ibu. Sofia and Mrrs. Jane gave me an inputs about the comparisen of the cost. their inputs are to buy all the compost from different brand of comppost either its fake or the real thing. and later I will try it on my plants which one will grow faster. ten I will mark take note of it and on the exhibition day I will show the brands which one has good and bad quality or fake or real. hope I get good result. and to test it I will ask my primary resource of how to test it.