1. An electric rocket is to be designed to provide a Aut of 5.7 km/s. Given that the "burn" time is 90 days, and (a) is 10 kg/kW, calculate the optimum specific impulse, and the corresponding (ML/MO). Furnish either a table or a plot of Isp-(ML/MO) values to support your conclusion and highlight the necessary information in it. {Ans.: 3700s} 2. Reconsider Problem 1. If the specific impulse is selected to be 80% of the optimum value, and (ML/MO) is maintained at the optimum value, what value of Au, will be achieved? {Ans.: 5.5 km/s} 3. Reconsider Problem 1. If the value of (a) is reduced to 5 kg/kW, what will be (ML/MO) at the optimum specific impulse value of Problem 1? Is this the optimum specific impulse with the new (a)? If not, what is the new optimum and the corresponding (ML/MO)? Again, provide either a table or a plot of Isp-(ML/MO) values to support your conclusion, and highlight the necessary information in it. {Ans.: 0.7931, first part}