Factor the GCF: −12x4y − 9x3y2 + 3x2y3 (5 points) 3x2y(−4x2 + 3xy − y2)
−3x2y(4x2 + 3xy − y2)
−3(4x2y + 3x3y2 − x2y3)
−3x2y(−4x2 − 3xy + y2)

Yes you are right the correct answer is b

When rates are expressed as a quantity of 1, such as 2 feet per second or 5 miles per hour, they are called unit rates. if you have a multiple-unit rate such as 120 students for every 3 buses, and want to find the single-unit rate, write a ratio equal to the multiple-unit rate with 1 as the second term.