How do I solve for:

B=.10(90,000-.40(90,000-B))

and

B=.10(90,000-.40(90,000-.40(90,000- B)-B)

If x-1 and x+3 are the factors of x3+10x2+ax+b find a and b

The cost of turkey is directly proportional to its weight. if a 12-pount turkey costs $27, how much does a 13-pound turkey cost? a. $33.75 b. $36.00 c. $31.00 d. $32.50

The radius of the sphere is 10 units .what is the approximate volume of the sphere use π=3.14