A term structure model with no drift and normally distributed rates can be defined by the equation $dr = \sigma dw$.

Given:

• Short rate $r = 5\%$
• Annual volatility $\sigma = 75 \text{ bps} = 0.0075$
• Realization of $dw = 0.2$

The change in the short-term interest rate is calculated as: $dr = 0.0075 \times 0.2 = 0.0015 = 0.15\%$

Thus, the new spot rate is: $r_{new} = 5\% + 0.15\% = 5.15\%$