An ideal gas of density `rho=0.2 kg m^(-3)` enters a chimney of height ℎ at the rate of `alpha =0.8 kg s^(-1)` from its lower end, and escapes through the upper end as shown in the figure. The cross-sectional area of the lower end is `A_1 =0.1 m^2` and the upper end is `A_2 = 0.4 m^2` The pressure and the temperature of the gas at the lowerend are 600 ?? and 300 ?, respectively, while its temperature at the upper end is 150 k . The chimney is heat insulated so that the gas ` gamma =2` . Ignore atmospheric pressure .

Which of the following statement(s) is(are) correct?

Options

A. The pressure of the gas at the upper end of the chimney is 300 p a.
B. The velocity of the gas at the lower end of the chimney is 40 `m s^(-1)` and at the upper end is `20 ms^(-1)`
C. The height of the chimney is 590 m.
D. The density of the gas at the upper end is 0.05 kg` m^(-3)`