Answer: 30 m/s
Explanation:
Use the first kinematic equation for linear motion

94.20 g/3.16722 mL = 29.74 g/mL
The ratio of mass to volume is equal to the substance's density. Thus, 29.74 g/mL is the density of whatever substance it may be. Density does not change for incompressible matter like solid and some liquids. Although, it may be temperature dependent.
If you have a book, read it!! I promise you, it tells you this answer!
As a conjugate base of a strong acid,ClO4-would be classified as having a negligible basicity. The basicity of a chemical species is normally expressed by the acidity of the conjugate acid. The basicity of an acid is the number of hydrogen ions, which can be produced by one molecule of the acid.
PH scale is used to determine how acidic or basic a solution is.
pH can be calculated as follows;
by knowing the ph we can calculate pOH
pH + pOH = 14
pOH = 14 - 8.1
pOH = 5.9
pOH is used to calculate the hydroxide ion concentration
pOH = -log[OH⁻]
[OH⁻] = antilog(-pOH)
[OH⁻] = 1.26 x 10⁻⁶ M
therefore hydroxide ion concentration is 1.26 x 10⁻⁶ M