1. a new marketing approach will not change the number of units sold

a. Null hypothesis

b. Directional hypothesis

c. Non-directional hypothesis

2. The performance of 50 students in the initial test will differ significantly from their performance in the final test

a. Null hypothesis

b. Directional hypothesis

c. Non-directional hypothesis

3. a wholesome advertisement will lead to increased sales for the product

a. Null hypothesis

b. Directional hypothesis

c. Non-directional hypothesis

4. There is a difference in the durability of two different brands of watches

a. Null hypothesis

b. Directional hypothesis

c. Non-directional hypothesis

5. Children using brand A tooth have fewer cavities than those using brand B toothpaste

a. Null hypothesis

b. Directional hypothesis

c. Non-directional hypothesis