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Read the passage given below and answer the following questions:
When haloalkanes with $\beta-$hydrogen atom are boiled with alcoholic solution of KOH, they undergo elimination of hydrogen halide resulting in the formation of alkenes. These reactions are called $\beta-$elimination reactions or dehydrohalogenation reactions. These reactions follow Saytzeff's rule. Substitution and elimination reactions often compete with each other. Mostly bases behave as nucleophiles and therefore can engage in substitution or elimination reactions depending upon the alkyl halide and the reaction conditions.
The following questions are multiple choice questions. Choose the most appropriate answer:

1. Among the following the most reactive towards alcoholic $KOH$ is:

1. $CH_2 = CHBr$
2. $CH_3COCH_2CH_2Br$
3. $CH_3CH2Br$
4. $CH_3CH_2CH_2Br$

2. The general reaction, $\text{R}-\text{X}\xrightarrow{\text{aq.OH}^-}\text{ROH}+\text{X}^-,$ is expected to follow decreasing order of reactivity as in:

1. $t-BuI> t-BuBr > t-BuCI > t-BuF$
2. $t-BuF > t-BuCI > t-BuBr > t-BuI$
3. $t-BuBr > t-BuCI >t-BuI> t-BuF$
4. $t-BuF > t-BuCI > t-BuI > t-BuBr$

3. Reaction of t-butyl bromide with sodium methoxide produces:

1. Sodium t-butoxide.
2. t-butyl methyl ether.
3. Iso-butane.
4. Iso-butylene.

4. In the elimination reactions, the reactivity of alkyl halides follows the sequence:

1. $R - F > R - CI > R - Br > R - I$
2. $R - I > R - Br > R - Cl > R - F$
3. $R - I > R - F > R - Br > R - CI$
4. $R - F > R - I > R - Br > R - CI$

5. The ease of dehydrohalogenation of alkyl halide with alcoholic $KOH$ is:

1. $3^\circ < 2^\circ < 1^\circ$
2. $3^\circ > 2^\circ > 1^\circ$
3. $3^\circ < 2^\circ > 1^\circ$
4. $3^\circ > 2^\circ < 1^\circ$