Abox contains four red balls and eight black balls. two balls are randomly chosen from the box, and are not replaced. let event b be choosing a black ball first and event r be choosing a red ball second. what are the following probabilities?

Name each raycalculation tip: in ray "ab", a is the endpoint of the ray.

Factor the polynomial by its greatest common monomial factor.

The bottom of ignacio's desktop is 74.5cm from the floor. ignacio's sits in his adjustable chair, and the tops of his legs are 49.3cm from the floor. each clockwise rotation of the knob on the chair raises ignacio's legs by 4.8cm. write an inequality to determine the number of clockwise rotations, r, ignacio could make with the knob without his legs touching the desk