To find the maximum frictional force, we can use the formula:
\[ f_{max} = \mu_s \cdot N \]
where \( f_{max} \) is the maximum frictional force, \( \mu_s \) is the coefficient of static friction, and \( N \) is the normal force.
Given:
- \( \mu_s = 0.35 \)
- \( N = 80 \) newtons
Substituting the values:
\[ f_{max} = 0.35 \cdot 80 \]
Calculating this:
\[ f_{max} = 28 \text{ newtons} \]
So, the maximum frictional force of the surface acting on the object is B. 28 newtons.