How can you tell whether a graph shows a proportional relationship? I WILL GIVE BRAINLIEST IF ONLY UR CORRECT

Which of the following parabolas opens up?

Grading scale 1 has the following weights- (tests- 50% quiz- 25% homework- 15% final exam- 10%). calculate your final average if your performance in the class is as follows-test grades- {88, 84, 90, 75, 70, 81); quiz grades- {88, 67, 90, 90, 45, 99, 76, 98, 100}; homework- 90; final exam- 75

Arectangular garden measures 5m by 7m. both dimensions are to be extended by the same amount so that the area of the garden is doubled. by how much should the dimensions increase, to the nearest tenth of a metre?