What is the value of 3ab+5b-8 when a=-1 and b=3?

The price of an item has been reduced by 30%. the original price was $30. what is the price of the item now ?

The circumference of a redwood tree trunk is 20π ft, and it is 100 ft tall. what is the approximate volume of the redwood tree trunk? 1,000π ft3 10,000π ft3 4,000π ft3 40,000π ft3

Karen will divide her garden into equal parts. she will plant corn in 8/12 of the garden. what is the lowest number of parts she can divide her garden into?