Market researchers sent an opinion survey to every twenty-fifth person who ordered a subscription to a weekly news magazine. the researchers were most clearly employing a technique known as:

random sampling

Explanation:

Random sampling -

As can be determined from the word , the sampling which is done on the random fashion , is random sampling.

It is the method , by which some samples are distributed to certain random people or object from a group of people or object , is referred to as random sampling.

It is also known as probability sampling.

Hence ,from the given scenario of the question ,

The correct term is random sampling.

the correct answer is 2.

a slump in geology means a mass movement process of slope failure. a mass of rock or unconsolidated material drops along a slip surface. in other words, rock layers move a short distance down the slope. the slump block is an intact block (2), without any landslide material.

in this image, 1 is the surface of rapture (scarp), 2 the slump block, 3 main scarp (crown), 4 base of rapture with debris flow.

slumps are caused by clear cutting on unstable soils and the sagging of earth, in coastal areas they are due to wave infiltration.

d is the correct answer.

b is incorrect because it makes food by itself

c is incorrect because us humans don't know how to produce their own food using the sun like plants.

a is incorrect because consumers can depend on carnivores for eating food for consumers to eat the dead organism. same thing with omnivores.