Nitrogen
oxygen
argon
carbon dioxide
We know that the ball falls under the influence of gravity. Hence, we can assume that its motion is with constant acceleration and it is in a line.
The equation for this kind of motion is:

where s is the distance and g is the acceleration. Since we know that for t=2 sec, s=60m, we can find the acceleration g. Substituting, we get: 60= g*(1/2)*2*2 hence g=30m/s^2 (these are the units of acceleration).
Now, we need to find the time in which the ball drops 120 m. So we substitute s=120m and we know the acceleration. We get then:
120=30/2 *t^2.
Hence, solving for t^2, 240/30=t^2, t^2=8. We get that t=

.
It is interesting to notice, that while the distance has doubled, the time has not; the time has only gotten larger by a factor of 1.4
Answer:
This question is unclear but the answer is:
the color of the con
Explanation:
In an experiment, the independent variable is the variable that is changed or manipulated by the experimenter to achieve a measurable response.
In this experiment which involves a student that notices that wearing care colors insight makes him feel warmer se. He decides to conduct an experiment by manipulating the colors of the cares, hence, the color of the con is the independent variable.
Answer:
Finding land for wind farms
Answer:
I believe c.
Explanation:
by process of elimination.