Units and Dimensions

In a given system of units, the ratio of the unit of volume to the area gives the unit of :
A micrometer screw gauge has a negative error of 7 divisions. While measuring the diameter of a wire the reading on main scale is 2 divisions and $$78^{th}$$ circular scale division, coincides with base line. The number of divisions on main scale are 10 to a centimetre and the circular scale has 100 divisions.
A liquid of low specific heat capacity is preferred as a thermometric liquid.
Ramu applied a force of 10 N on a body to move it from rest. He wants to express the applied force is in terms of various system of units.
What is dimensional formula for magnetic flux densities?