C. They have adapted to low temps and harsh winds.
The first answer choice is correct: SF6 is a compound: it is a substance composed of more than one atom from different elements (sulfur and fluorine).
The second answer choice is incorrect: while SF6 is indeed a compound that contains seven atoms, those atoms are not identical since one is a sulfur atom and six are fluoride atoms.
The third answer choice is incorrect: SF6 is not an element because it can be separated chemically into simpler substances that are elements. All the atoms comprising an element must have the same number of protons (the same atomic number); sulfur and fluorine have different atomic numbers. There is no single nucleus in SF6; the S and six F atoms each has their own nucleus.
The fourth answer choice is incorrect; SF6 contains no carbon atom, and so wouldn’t meet a central criterion for an organic compound. Moreover, the formula SF6 indicates that the sulfur atom is not bonded to any other atom apart from fluorine atoms, and there are no bonding electrons left on the S. There is no plausible reason to think that a molecule with such weak intermolecular attractions as SF6 would form long chains of S atoms. Indeed, in standard conditions, SF6 is a gas.
Answer:
D
Explanation:
The answer will be D because as we can deduct from the hypothesis, he will try to control the amount of food he gives the rats in order to see if in fact the fue of the mouse will be shinier
Explanation:
Oxidizing agents are defined as the agents which oxidize other substance and itself gets reduced. These agents undergoes reduction reactions.
Reducing agents are defined as the agents which reduces the other substance and itself gets oxidized. These agents undergoes reduction reactions.
When oxidizing agent-A get reduced it changes green to colorless.
When oxidizing agent-B get reduced it changes yellow to colorless.
When oxidizing agent-C get reduced it changes red to colorless.
1) When we added solution C that oxidizing agent-C in solution containing 
ions changes from red to yellow:
So, in this C is oxidizing ion into B which yellow in color.
C is reduced and ions is oxidized.
Here, are oxidized by C which means that C a better oxidizing agent than B.
2) When a solution of C is mixed with one containing A- ions, the color remains red.
no reaction
As we had observed that no color change was seen on adding substance C to the solution with 
ions which indicates that C was unable to oxidize ions. Hence, not a better oxidizing agent than A
