Four wires with currents are arranged in the corners of a square. Current in the upper left corner (as viewed from your point of view) is 2I, all others are I. Direction of all currents is out of a page (towards you). The direction of net magnetic field in the center of a square is:
a. towards the upper right corner
b. towards the upper left corner
c. towards the lower right corner
d. towards the lower right corner
e. magnetic field is zero in the center

a I.e

 towards the upper right corner

Explanation:

A wire carrying electric current will produce a magnetic field with closed field lines. In the direction of the current, and the fingers curl in the direction of the magnetic field loops  

If we take the four sides of square as four separate current carrying wires , if we apply Fleming's left hand rule to find the force on each side , we find that ,forces will not be equal due to un even value of current.

magnetic force on each side will be

F = ILBsin 90

Making B the subject of the formula, we will found out that its direction will move towards the upper right corner

this allows people to make the best decision or pursue the best option. when alternatives are weighed using their advantages and disadvantages, the option whose disadvantages outweigh the advantages (based on a qualitative or quantitative analysis) are shunned while those whose advantages outweigh their disadvantages are pursued.  

the skeletons of most mammals reach a certain size and then stop growing. however, many animals, including some mammals, keep growing throughout their lives. kangaroos, for example, just keep growing and growing until they die. also, the longer an animal lives the greater the chance it might catch some deadly disease.