Answer:
C. φ
Step-by-step explanation:

Thus
can replace x
Answer:
a. 
b. $225
Step-by-step explanation:
Let Mr. Scruggs got money for his birthday be 'a'
He spent
of it on dog treats = a × 
= 
remainder amount would be = a - 
= 
Then he divided the remainder money equally among 3 favorite charities.

= 
a. Each charity receive
b. If he donated $60 to each charity.


a = $225
Mr. Scruggs received $225 for his birthday.