Which is a suitable method to decrease friction?

What force should be applied on the wedge so that the block over it does not move? (All surfaces are smooth)

Which one of the following statements is incorrect?

Provide an example from daily life where motion is controlled or initiated by an external force.

$A$ block of mass $m$ is suspended by a light thread from an elevator. The elevator is accelerating upward with uniform acceleration $a$. The work done by tension on the block during $t$ seconds is $(u = 0)$.

$A$ horizontal force $12 \, N$ pushes a block weighing $1/2 \, kg$ against a vertical wall. The coefficient of static friction between the wall and the block is $0.5$ and the coefficient of kinetic friction is $0.35$. Assuming that the block is not moving initially,which one of the following choices is correct? (Take $g = 10 \, m/s^2$)