Answer:
A) 
Explanation:
Since a = g - bv,
We can substitute a = dv/dt into the equation.
Then, the equation will be like dv/dt = g - bv.
So we got first order differential equation.
As known, v = 0 at t = 0, and v = g/b at t = ∞.
Since 
⇒ 
So take the integral of both side.
Since for t=0, v = 0 ⇒ 
Answer:
Ethyne consists of a triple bond that is most easier to be broken as compared to that of ethyne with a double bond and benzene single bonds. Therefore ethyne is most reactive among the given options.
Explanation:
Answer:
An estimate for the time it will take for a spacecraft to travel from Earth to Mars is approximately 138.8 days
Explanation:
The distance between Earth and the Moon = 684,400 km
The distance between Earth and Mars = 220.58 × 10⁶ km
The distance between Earth and Pluto = 5.2241 × 10⁹ km
The ratio of the distance between Earth and Pluto and the distance between Earth and Mars = (5.2241 × 10⁹ km)/(220.58 × 10⁶ km) ≈ 23.683
It took 2006 to 2015 (9 years) to travel from Earth to Pluto, therefore, it can take approximately (9 years)/(23.683) ≈ 0.38 of a year which is ((9 years)/(23.683)) × 365.2422 ≈ 138.8 days for a spacecraft to travel from Earth to Mars
