In a controlled experiment a scientist is studying how long it takes a parachute of different sizes to fall to the ground what is the manipulated variable

The correct answer will be- size of the parachute.

Explanation:

A scientific experiment is performed to test the hypothesis if it could be proved or not.

An experiment must include all the variables mentioned in the hypothesis which can be categorized as the variable which can be manipulated called the independent variable and the variable which has to be tested called the dependent variable.

In the given question, the variable to be tested (dependent variable) is the time required by the parachute to fall on the ground and the variable which could be manipulated (independent variable) will be the size of the parachute in the experiment.

Thus, the size of the parachute is the correct answer.

d concave shape of wave rock

explanation:

the concave shape of wave rock is a very good evidence that supports the evolution of earth due to chemical weathering. if we talk about structure of   wave rock, studies have estimated that it is around 2.7 billion years old. it also serves as the foundation of evidence that it was the place where australian continent began to form.

how the structure of wave rock was created?

studies suggest that structure of wave rock was created when the surrounded area was started to weather due to which deposition of material started on the part of land which now contains wave rock.

the structure of wave rock is considered to be one of the best-known landforms in australia. at the height of around 15 cm, there can be found flared slopes which formulate the margins of hyden rock. it is now assumed by geologists that wave rock was created by subsurface water-induced weathering and not by glaciers, waves or wind.

due to deposition of material over the period of long time, the wave rock became tougher and tougher due to weathering from surrounding terrain. this makes it a physical evidence that supports   the evolution of earth due to chemical weathering.

hope it !

answer: accepted answer: aquatic animals use the oxygen dissolved in water to carry out respiration. since the amount of dissolved oxygen in water is low as compared to the amount of oxygen in the air, therefore the rate of breathing in aquatic animals is much faster than it is in terrestrial animals.

explanation: