Halogens is defined as the group of 7 periodic table. As, every periodic table contains 7 valence electrons and they only need 1 more to complete an outer shell, that is why they are extremely reactive. And according to the law that recurring patterns of the properties of elements arise when they are arranged in order of increasing atomic number. As the halogen all act very similarly with each other in chemical reaction, it is true.
Answer:
C. to explore the composition of Mars
Explanation:
Initially, in 2019, an unmanned mission is planned to orbit the moon. The spacecraft would flyby the moon. In 2020's, the Exploration Mission 2 would be a manned mission on the same path around the moon. This would be the base for future goal of collecting samples from mars. In later of 2020's unmanned spacecraft would be sent to mars and a robot would collect the samples from the Martian surface. In 2030's, a crew would be sent to Mars.
Scientists repeat experiments for reliability. Experiments have to be repeated, since performing an experiment only once, does not prove a scientists theory on the experiment, which they develop by performing the experiment. And then performing the experiment again or even many times to prove or disapprove their theories. Btw, before an experiment begins, the scientist will make a hypothesis of what they believe will happen. If proven correctly, they would then use those results they record throughout the experiment, from beginning to end to prove whether or not their hypothesis are correct or incorrect. Click to let others know, how helpful is it
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So that they can prove the other scientists views wrong and develop a new theory in which there is more sense and credibility.
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BASICALLY, I THINK THE ANSWER IS 1 OR 2 OR
Answer:
turtle
Explanation:
they are slow and they take there time
