I have a difficulty with indicators of theory of planned behavior. I would like to know when measuring attitude, can I mix the questions like affective and beliefs about the consequences of outcomes. For example my questions are like

Practicing 3Rs principle in the use of plastic is a good.

Practicing 3Rs principle in the use of plastic is worthwhile.

Practicing 3Rs principle in the use of plastic is useful.

Practicing 3Rs principle in the use of plastic reduces environmental degradation.

Practicing 3Rs principle in the use of plastic preserve natural resources.

Practicing 3Rs principle in the use of plastic minimizes the amount of waste that needs to be disposed of at landfill.

I would like to know it is ture or not?

The next question is the indicators of social media. My purpose is to assess whether social media has impact on intention to practice 3Rs. Should it be influence of social media or social media usage or just social media? And what kinds of indicators should I use?

Thank you for your suggestions and kindly appreciate.