Answer:
declaration = - 0.55 m/s²
Step-by-step explanation:
The declaration is a negative accelaration.
Therefore:
[tex]a = \frac{v-u}{t}[/tex]
a = ?
v = 70 of 15% = 10.5 km/h to m/s = 2.9 m/s
u = 70 km/h to m/s = 19.4 m/s
t = 30 seconds
[tex]a = \frac{2.9-19.4}{30}\\[/tex]
a = - 0.55 m/s²