Arrange the following alkenes in the decreasing order of stability:
(I) `CH_(3)-overset(CH_(3))overset(|)C=CHCH_(3)`
(II) `CH_(3)-overset(CH_(3))overset(|)(CH)-CH=CH_(2)`
(III) `CH_(2)=CH-CH_(2)-CH_(3)`

Explanation

To arrange the given alkenes in decreasing order of stability, we need to analyze the number of alpha hydrogens present in each alkene. The stability of alkenes is directly proportional to the number of alpha hydrogens due to hyperconjugation. Here’s how we can determine the stability step by step:

### Step 1: Identify the Alkenes
We have three alkenes to analyze:
1. Alkene I: `CH3-C(CH3)=CH-CH3`
2. Alkene II: `CH3-C(CH3)(CH)=CH2`
3. Alkene III: `CH2=CH-CH2-CH3`

...