The answer is most likely that the answer is B. Because Space is a dangerous place in which you need certain things to explore it. If you want to go to to Jupiter, for example you need lots of Oxygen, fuel, a good rocket, willing people and many more things, but there is a way technology can skip all that. the technology we have now is not capable of doing that though.
First, let's explain the variables. F means force, m means mass, and a means acceleration. F is measured in Newotns [N], mass is measured in kilograms [kg], and acceleration in measured in meters per squared second [m/s²].
Now let's mover on the first problem.
Given
m = 1000 kg
a = 3 m/s²
According to the second law of Newton, the force is equal to the acceleration multiplied by the mass.

The answer is 3000 N.
The second problem is smiliar.
Given
m = 70 kg
F = 250 N
We use the same formula from before, and use a bit of algebra to adapat it to our needs.

The answer is 24 1/7 s/m^2.
Answer:
it is an exothermic reaction
Answer: D
Explanation:
A reducing agent is a species that reduces other compounds, and is thereby oxidized. The whole compound becomes the reducing agent. In other words, of a compound is oxidized, then they are the reducing agent. On the other hand, if the compound is reduced, it is an ozidizing agent.
Since we have established that a reducing agent is the compound being oxidized, we know that A is not our answer. An oxidized compound is losing electrons. Choice A states exactly this.
For B, this is true as we have established this already.
C is also correct. Since a reducing agent loses electrons, it becomes more positive. This makes the oxidation number increase.
D would be our correct answer. It is actually a good oxidizing agent is a metal in a high oxidation state, such as Mn⁷⁺.