A block of mass 2 kg is placed on an inclined plane which makes an angle of 30 with horizontal . The coeficient of friction acting is root3/2 then

1 The force to be applied on the block moves down without acceleration is ?
a) 10N
b) 15N
c) 5N
d) 20N
2 The ratio of powers needed in the above two cases if the speed of block is same in both cases is ?
a) 1:1
b) 1:2
c) 1:5
d) 2:1