Normal force

My problem is that I need to determine the normal force of the inlcine on the block.

The coefficient of static friction between the block and incline is mu^s = .295.

I have determiend that the minimum value of  "F" is 18.49 N.

I understand that   "F" * sin (59.5) would be my answer to determine the normal force, yet I keep struggling on determining  "F".  Please help