Suppose you ask all the students who are failing a class if they believe the course is too difficult, and you find that they indeed think it is. Although you have conducted a basic survey, the results of it are limited because of your sample.

1. efficient use of space

2. elimination of groundwater contamination

3. energy generation

4. lower carbon footprint

chert is a sedimentary rock composed of microcrystalline or cryptocrystalline silica. with this little bit of information, you can come to the conclusion that your answer is c.  

explanation:

sex cells are usually half's then they find another half and make a fertilize egg

1)

i))the process of preparing food by green plants in the presence of sunlight is called photosynthesis.

ii) leaf is the site for photosynthesis.

iii) it takes place as,

6h2o+6co2=c6h12o6+602