Please post the question with an attachment of what you want to be answered next time.
Answer:

Step-by-step explanation:
c varies jointly with d and the square of g


where, k is constant of proportionality.
Put the given value c = 30 when d = 15 and g = 2 and find out k


If c = 6 and g = 8 then d = ?



Hence, The value of d is 
Answer:
5 people
Step-by-step explanation:
3.50 + 5.50 = $9 per person
51 - 6 = 45
45/9 = 5
Answer:
B. 7/30
Step-by-step explanation:
1st time to pick red is 8/16 8 red cubes out of 16 are red
2nd time to pick red is 7/15 7 red cubes out of 15 are red,
*if one red is picked already
8/16 x 7/15 = 7/30