Answer:
A. Mass(only)
Explanation:
The correct answer is A because if the balloon is filled with air, it's filled with matter. Matter is anything that has space and occupies mass. The air occupies mass in the balloon but that doesn't mean that the balloon is heavier. People confuse themselves with mass and weight saying it means the same thing. Mass, like I said is the amount of matter an object contains whereas weight is how much an object weighs.
There are two ways to solve this. The longer way is to use those equations to calculate numbers for total distance.
The easier way is to find the area under the graph. That's right, AREA UNDER VELOCITY-TIME graph is the TOTAL DISTANCE travelled!
it's a shortcut.
Let's split up the area into a triangle and rectangle:
Triangle = 0.5(4-0)(10-0) = 20 m
Rectangle = (6-4)(10-0) = 20 m
Total distance = 40 m!
Answer:

Explanation:
The magnitude of the electric field between two parallel conducting plates is defined as:

Here
is the potential difference between the plates and d its separation.
The electric potential energy is defined as the product between the particle's charge and the potential difference:

Solving for
and replacing in the electric field formula:

In this case we have a double charged ion, so
:

Answer is in the photo. I can only upload it to a file hosting service. link below!
tinyurl.com/wpazsebu