Define the terms hybridization and photoperiod.

Define $(i)$ Vermicompost,$(ii)$ Green manure,and $(iii)$ Biofertilizer.

Fill in the blanks:
$(a)$ Photoperiod affects the . . . . . . .
$(b)$ Kharif crops are cultivated from . . . . . . to . . . . . . .
$(c)$ Rabi crops are cultivated from . . . . . . to . . . . . . .
$(d)$ Paddy,maize,green gram,and black gram are . . . . . . crops.
$(e)$ Wheat,gram,pea,and mustard are . . . . . . crops.

Rajan and his family members were going to Dalhousie in a car to enjoy their weekly holidays. While on the way,it started raining. During the journey,Rajan observed that when another vehicle or bus passed them and honked,the intensity of the sound produced was higher than it would be in an area without rain.
$(a)$ What,according to you,is the reason behind the increase in the intensity of sound during rain?
$(b)$ What value do you attribute to Rajan's observation?

The preventive and control measures which are used before grains are stored for future use include:

Neem and turmeric powders are often used in grain storage.
$(i)$ What are they called?
$(ii)$ What is the purpose of using neem and turmeric?
$(iii)$ What are herbicides?