Consider an air-standard Brayton cycle with adiabatic compressor and turbine, and a regenerator, as shown in the figure. Air enters the compressor at 100 kPa and 300 K and exits the compressor at 600 kPa and 550 K. The air exits the combustion chamber at 1250 K and exits the adiabatic turbine at 100 kPa and 800 K. The exhaust air from the turbine is used to preheat the air in the regenerator. The exhaust air exits the regenerator (state 6) at 600 K. There is no pressure drop across the regenerator and the combustion chamber. Also, there is no heat loss from the regenerator to the surroundings. The ratio of specific heats at constant pressure and volume is $c_p/c_v$= 1.4. The thermal efficiency of the cycle is ________% (answer in integer).

If ‘→’ denotes increasing order of intensity, then the meaning of the words
[smile → giggle → laugh] is analogous to [disapprove → _______ → chide].
Which one of the given options is appropriate to fill the blank?

Find the odd one out in the set: {19, 37, 21, 17, 23, 29, 31, 11}

In the following series, identify the number that needs to be changed to form the Fibonacci series.

1, 1, 2, 3, 6, 8, 13, 21, …