Final answer:
The value from the spinner that would allow all 4 contestants to win a prize is 90°, as it divides the circle into 4 equal parts.
Step-by-step explanation:
The student has asked which value from the spinner would allow all 4 contestants to win a prize. The available options are 30°, 90°, 180°, and 270°. To ensure that all 4 contestants win a prize, the angle when the spinner stops must divide the circle equally into 4 parts. In other words, the angle must be such that it can go into 360° a whole number of times, which is true for 90° since 360° / 90° is exactly 4.
Therefore, the correct answer is b) 90°, because a circle has 360°, and dividing this by 90° gives exactly 4 equal segments, one for each contestant.