Question : In which situation, PPC can be a straight line due to:

Option 1: Decreasing

Option 2: Constant

Option 3: Increasing

Option 4: None of the above

Question : Which trend is found about the distance between the galaxies?

Option 1: Constant

Option 2: Increasing

Option 3: Unpredictable

Option 4: Decreasing

Question : Due to the greenhouse effect:

Option 1: the temperature of the Earth is decreasing

Option 2: the temperature of the Earth is increasing

Option 3: the temperature of the Earth is constant

Option 4: No option is correct

Question : An object covers distance which is directly proportional to the square of the time. Its acceleration is:

Option 1: increasing 

Option 2: decreasing

Option 3: zero

Option 4: constant

Question : When all inputs are doubled and a result, output also doubles, then we have:

Option 1: constant returns to scale

Option 2: decreasing returns to scale

Option 3: increasing returns to scale

Option 4: none of the options