The first is C. The second is A.
A: rhombus and squares have four equal sides.
Answer:
1 : 30
Step-by-step explanation:
300mm:9m
We need to change the meters to mm
1 meter is 1000 mm
so 9 m is 9000 mm
300mm:9000mm
Divide both sides by 300
300mm/300 : 9000/300
1 : 30
Solution :
It is given that :
Number of students in a random sample majoring in communication or psychology at an university = 250
Total number of students majoring in psychology = 100
Number of students majoring in psychology those who are happy = 80
So number of students majoring in psychology those who are not happy = 20
Total number of students majoring in communication = 250 - 100 = 150
Number of students majoring in communication those who are happy = 115
So number of students majoring in psychology those who are not happy = 35
a). Probability of the students happy with their major choices are

= 0.78
b). Psychology major 
= 0.4
c). Probability of the students who are happy with the communication as the choice of major =
= 0.46
d). Students unhappy with their choice of major given that the student is psychology major =
= 0.018
It’s the first one. I think