Metal sphere a has a charge of -2 units and an identical sphere b has a charge of -4 units. if the two spheres are brought together and then separated, the charge on sphere a will
a) -3 units
b) +4 units
c) 0 units
d) -2 units
*if you can also explain how this is done when answering that would be great : )

v = 4.76 m/s

Explanation:

Given,

The distance traveled by her bike, d = 10 miles

The time of her travel, t = 2.1 m/s

The velocity of an object is defined as the distance traveled by the object to the time of travel. Therefore,

                          V = d/t   m/s

                              = 10 / 2.1

                              = 4.76 m/s

Hence, The velocity of her bike is, V = 4.76 m/s