Answer:
hour and a half
Step-by-step explanation:
Answer: 3
Step-by-step explanation:
Let E be the event of that student pierces ear and N be the event of that student pierces nose.
Given: 

For any two event A and B, we have

Similarly , 

Hence, 3 students have piercings both on their ears and their noses.
A triangle always adds up to 180 degrees:
Therefore, 48 + 6x + 9x-3 = 180
Solve for x:
180 - 45 = 15x
135 = 15x
x = 9 degrees
Acute is the answer ..........