Answer:
Five: B
Ten: A
Explanation:
Five
An alpha decay looks like this.

So whatever is produced must have a mass of 4 less than 234 and a number on the periodic table of 2 less than 92. In other words, B has a mass of 230 and a number on the periodic table of 90.
The answer should be Thorium which is B.
Ten
There is actually not enough information to do 10. You get it by making an assumption and seeing if it works.
In general a beta decay can (the most common one ) look like this.

Is there anything that looks like that?
The weight stays the same (234) and the atomic number of the mother element (on the left) is 1 lower than the given chemical on the right.

The answer is Thorium A
Beta decays are very tricky. Be very careful how you handle them. One of three items can be what is decayed. I have assumed it was an electron, but there are two other possibilities. I won't confuse you by adding them. Just be aware that they exist.
Answer:
2 m/s²
Explanation:
Given:
v₀ = 0 m/s
v = 20 m/s
t = 10 s
Find: a
a = (v − v₀) / t
a = (20 m/s − 0 m/s) / 10 s
a = 2 m/s²
From the formula: density=mass/volume
But first, we have to convert the cm³ to m³ by multiplying the value in cm³ by 10^-6, by so doing we'll have the volume to be 0.48*10^-3cm³.
we will also need to convert the mass which is in g to kg by simply dividing by 1000 so the mass becomes 0.12kg
Now we can solve for the density using the formula I earlier stated which is the mass divided by the volume =0.12/0.48*10^-3 so the density will be 0.25*10^3kgm-3 or 2.5*10^2kgm-3
I think it is because in objects that reflect light, the light is bounces/reflects off the object in one direction and one angle, and hits your eye, causing it to be processed as a reflection of yourself in your brain. But in one that scatters light, it bounces/reflects off in many different directions. Due to this, your brain may not process it as a reflection.
Here is a little bit of extra info:
https://www.sciencelearn.org.nz/resources
The answer is D.nitrogen. the atmosphere is mostly made up of nitrogen.(95% is nitrogen) and (2% <span>oxygen</span>) and and (3% of other gases)