Respiratory
Circulatory
Muscular
Answer:
I'm no expert, but multitasking is a no bueno. Because multitasking reduces your efficiency and performance because your brain can only focus on one thing at a time. When you try to do two things at once, your brain lacks the capacity to perform both tasks successfully.
Therefore I would choose A, considering he could easily workout another time, whilst the test is a one time thing. He can't redo the test, but he can workout again. So my answer is A.
If he HAS to workout and study at the same time, then C would be appropriate.
I hope this helps!
I believe it is the percent abundance. Isotopes are atoms of the same element with similar atomic number but different mass number. Natural abundance is the abundance of isotopes of a chemical element as naturally found on the planet. The relative atomic mass of these isotopes is the atomic weight listed for the element in the periodic table.
Answer:
C and D
Explanation:
Galaxies are composed of stars, dust and dark matter, all held together by gravity. Astronomers aren't certain exactly how galaxies formed. After the Big Bang, space was made up almost entirely of hydrogen and helium.