Figure shows two blocks in contact placed on an incline of angle `theta = 30^(@)`. The coefficient of friction between the block of mass 4 kg and the incline is m1, and that between 2 kg block and incline is `mu_(2)`. Find the acceleration of the blocks and the contact force between them if –
(a) `mu_(1) = 0.5 , mu_(2) = 0.8`
(b) `mu_(1) = 0.8 , mu_(2) = 0.5 `
(c) `mu_(1) = 0.6 , mu_(2) = 0.1 " "` [ Take `g = 10m//s^(2)`]