The Earth turns once on its axis in 24 hours…

Step 1. Period. $T = 24 \times 3600\ \text{s} = 86\,400\ \text{s}$.

Step 2. Angular velocity. $\omega = \dfrac{2\pi}{86\,400\ \text{s}} = 7.27 \times 10^{-5}\ \text{rad/s}$.

Step 3. Speed. $v = \omega r = 7.27 \times 10^{-5}\ \text{rad/s} \times 6.4 \times 10^{6}\ \text{m} = 465\ \text{m/s}$.

Step 4. Acceleration. $a = \omega^2 r = (7.27 \times 10^{-5}\ \text{rad/s})^2 \times 6.4 \times 10^{6}\ \text{m} = 0.034\ \text{m/s}^2$.