Density = Mass/Volume
d = .254/129.4
b the absence of a nucleus
Answer:

Explanation:
1 mole of any substance contains the same number of particles. The particles can vary (atoms, molecules, formula units), but there are always 6.022*10²³ particles. In this case, the particles are formula units of potassium nitrate or KNO₃.
Let's create a ratio.

Since we are trying to find the formula units in 0.250 moles, we multiply by that number.

The units of moles of potassium nitrate cancel.

The denominator of 1 can be ignored, so we can make a simple multiplication problem.


If we round to the nearest tenth, the 0 in the hundredth place tells us to leave the 5 in the tenth place.

0.250 moles of potassium nitrate is approximately equal to 1.5*10²³ formula units of potassium nitrate and choice B is correct.
Answer: a. A worm can move so it must be living.
Explanation:
If a worm is moving it is classified as a moving worm also known to be living if moving.
A worm could reproduce therefore it is living.
Worms do pass dirt into and through there bodies to eat of the minerals and discarding things through and let out.
If you do cut a worm in half it may damage it but since it has basically two heads on girl one boy and cut in half it may split them up, and make damage but they will eventually grow back if the injuries are not severe.
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Answer:
1 and 3
Explanation:
The vertical columns (groups) of the periodic table are arranged such that all its elements have the same number of valence electrons. All elements within a certain group thus share similar properties.