108 = -2(-5 - 7b) What does b equal?

If you have 12 feet of string and you cut it into equal length of 5 inches each how much string will be left

The ivring berlin learning center would like a possible net profit of $650,000 on its new resource manual it sells to schools. the fixed costs for producing the manual are $780,000 and the variable cost per package is $19.85. if the estimated unit sales are 1,250,000 units, what selling price unit should the ivring berlin learning center try?

Could someone me with this question i’ve been stuck on it for 20 minutes