Two capacitors of capacitance C_5 = 6.00 \rm \mu F and C_6 = 3.00 \rm \mu F are added to the network, as shown in the diagram. (Part B figure) Find the equivalent capacitance C_B of the new network of capacitors.

I don't see your diagram and I don't know what your \rm symbol is supposed to mean.

This is preswumably an exercise in computing the equivalent capacitance of a pair of capacitors in series or in parallel.

In parallel, the capacitances add.
In series, the reciprocal capacitances add.

To find the equivalent capacitance C_B of the new network of capacitors, we can use the following formula:

1/C_B = 1/C_5 + 1/C_6

First, let's substitute the values of C_5 and C_6 into the equation:

1/C_B = 1/6.00 μF + 1/3.00 μF

To add these fractions together, we need a common denominator. In this case, we can use 6.00 μF as the common denominator:

1/C_B = (1/6.00 μF) + (2/6.00 μF)

Now, let's combine the fractions:

1/C_B = (3/6.00 μF)

To simplify the equation further, we can invert both sides:

C_B = (6.00 μF) / (3/6.00 μF)

Dividing by a fraction is the same as multiplying by its reciprocal:

C_B = (6.00 μF) * (6.00 μF/3)

Multiplying the numerators and the denominators:

C_B = (6.00 μF * 6.00 μF) / 3
= 36.00 μF^2 / 3

Finally, let's simplify the expression:

C_B = 12.00 μF

Therefore, the equivalent capacitance C_B of the new network of capacitors is 12.00 μF.