Answer:
missing - biostatics
Explanation:
Longitudinal studies differ from one-off, or cross-sectional, studies. The main difference is that cross-sectional studies interview a fresh sample of people each time they are carried out, whereas longitudinal studies follow the same sample of people over time.
hope this helps :)
Answer:
The producers play main role in the food chain and food web as well. These organism make food by the help of the process known as photosynthesis.
Only producers have the ability to make food by trapping sunlight. All the living source needs energy to survive.
The source of food is producers so living things cannot survive without food. So there producers are considered as the main component of food chains and food web.
hence, they play a very vital role in the environment.
Example of multi cropping is tomatoes+onions+marigold
