Part A:
Each snowball costs $0.30 to make and is sold for $1.25 each.
The profit per snowball is:
P = $1.25 - $0.30 = $0.95
The profit is $0.95 per snowball
Part B:
Little brother gave away 12 snowballs. The student lost the profit of those 12 snowballs:
12 x $0.95 = $11.40
The student lost $11.40 in profits
Note: The student also lost the $0.30 for the cost to make each snowball, but it's not accounted for.