Sally and Maria hypothesized that earthworms lived only in dark, damp places. They measured a one-meter square in a shady spot near a stream. They dug through the soil and collected earthworms. They collected 43 worms. What should the girls do to reach a
valid conclusion for their hypothesis?
A)
Repeat the experiment in another shady spot.
B)
Nothing. They carried out a valid experiment.
Repeat the their steps in different locations, including sunny, dry, and wet.
D)
Repeat the dig on a larger area near the stream.

the element that provides strength to the exoskeletons of clams and oysters is phosphorus.

this is so because calcium carbonate is the main component in the shells. calcium carbonate is strengthened by phosphorus.

explanation:

evidence and logical support is essential for a scientist to do in order to maintain credibility. this is because no one can believe without any logic and without any evidence.hence a scientist can maintain credibility by proving himself and by answering logically so experiments prove very beneficial. logical hypothesis give conclusion which is acceptable. therefore, there are two main factors to maintain credibility by a scientist is evidence and logical support.

answer; hydrologic cycle;