Answer
a. 6.2 V
b. Step-down
Work Step by Step
a. By comparing equations 21-6 and 21–7, we see that the current ratio is the reciprocal of the voltage ratio. The current changed (increased) by the ratio of (6.8A/0.35A). The voltage must change by the reciprocal of the ratio, and become smaller.
$$V_{out}=(120V)\frac{0.35A}{6.8A}=6.2V$$
The output voltage is lower; this is a step-down transformer.