Can you please explain how to solve these problems?

I can't understxand the sign for the explanation CCW and CW how can they conclude like that by using that equation?

Thanks In advance.

1) A circular loop of wire is placed in a magnetic field that points into the page as shown. In order for NO induced current to be produced by this magnetic field, the magnetic field should A. Be increased in magnitude, but with no change in direction B. Be decreased in magnitude, but with no change in direction X B C. Be left alone at its present value D. Be decreased to zero E. None of these. There will always be an induced current from a field like this. 2) A standard motional emf setup in the xy consists of a constant, uniform magnetic field which points out of the page and has magnitude 0.25 T. The circuit's entire resistance is 2 Ohms at the location shown (on the movable rail). The movable rail (double-line on the right side of the circuit) is going left at a speed of 8 m/s. i. Which side of the resistor is at a lower electric potential due to the induction effect? A. Top B. Bottom Ad -, ind +, Bind Out, I ind CCW C. Both are equal but nonzero D. Both are zero li. The magnitude of the current through the resistor due to the induction effect will be A. 0.40 A B. 0.20 A C. 0.15 A D. 0.030 A E. Zero ili. Which way should the movable rail go so that 15 cm the induced current is counterclockwise? A. Left B. Right C. It should remain stationary D. None of these. There is no way a counterclockwise induced current can 20 cm 20 be created by moving the rail. B Ad -, ind +, Bind out, I ind CCW