The reaction of the half-life is a description of the needed time for the reactant to deplete.In the first order reactions formula, k is considered as the first order rate constant whose unit is denoted as 1/s. Hope this helps.
Answer:
0.1308
Explanation:
To keep the rider from sliding down, then the friction force
must at least be equal to gravity force 


where μ is the coefficient, N is the normal force acted by the rotating cylinder, m is the mass of a person and g = 9.81 m/s2 is the gravitational acceleration.
According to Newton's 3rd and 2nd laws, the normal force would be equal to the centripetal force
, which is the product of centripetal acceleration
and object mass m

Therefore


The centripetal acceleration is the ratio of velocity squared and the radius of rotation

Therefore

Thus 1 cm–3 = 1/cm3 and the units for our densities could be written as gcm3, g/cm3, or g cm–3. In each case the units are read as grams per cubic centimeter, the per indicating division.) We often abbreviate "cm3" as "cc", and 1 cm3 = 1 mL exactly by definition.
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1.9: Density.
The full valence shell means that they do not react in chemical bonding.
The main purposes of chemical bonding is to obtain a stable structure.
Since the valence shell is stable,there is no need for chemical bonding since the whole atom is stable.