What is the exact volume of the sphere? Sphere with dotted line extending from middle point of sphere to edge. Line is labeled six and one- half feet.

A. 56.3¯π ft³

B. 274.625π ft³

C. 366.16¯π ft³

D. 1464.6¯π ft³

Multiply. −2x(6x4−7x2+x−5) express the answer in standard form. enter your answer in the box.

Acable company wants to provide cell phone service for residents on an island. the function for the cost of laying the cable from the island to the mainland is c(x)= 6.500 square root x2+4, where x represents the length of the cable in feet. what are the domain and range of the function? a) domain: all real numbers range: all real numbers greater than or equal to 17,000 b) domain: all real numbers greater than or equal to 0 range: all real numbers greater than or equal to 17,000 c) domain: all real numbers greater than or equal to 0 range: all real numbers greater than or equal to 13,000 d) domain: all real numbers greater than or equal to 13,000 range: all real numbers greater than or equal to 0

Determine whether the set of whole numbers is closed under addition. explain why the set is or is not closed. give an example.