#### Answer

The rate of profit is approximately 33.3%

#### Work Step by Step

We can use the following guideline to solve this problem:
Rate of profit = $\frac{Selling\ price -\ Cost}{Cost}$ $\times$ 100%
Selling price = 56
Cost = 42
Substituting these values into the formula gives:
Rate of profit = $\frac{56-42}{42}$ $\times$ 100%
Rate of profit = $\frac{14}{42}$ $\times$ 100%
Rate of profit = 0.333333 $\times$ 100%
Rate of profit $\approx$ 33.3%