20+ ! answer !
which sets of numbers are closed under addition?
choose all answers that are correct.
a.
whole numbers
b.
natural numbers
c.
negative integers
d.
integers

Beatrice decides she wants to babysit a few children at the same time to earn the money faster. she tells parents that if they allow her to babysit their children at her house, she will eliminate her automatic $5 tip and will give them an additional $5 discount. (a) write an equation showing the total cost for each client. identify all variables. (b) four parents bring their children to beatrice’s house at the same time for babysitting. beatrice wants to find out how many hours she must babysit the 4 children to earn exactly the $100 she needs in order to buy the present for her mother. write and solve an equation to find the number of hours. justify each step in the solution. (c) one parent decides not to drop off her child. the remaining 3 parents drop their children off at 9 a.m. two of the parents say they will be back at 1 p.m. the third parent says she will pick up her child at 2 p.m. at noon, beatrice realizes she needs feeding the 3 ch

What is the value of x? enter your answer in the box. (cm)

Determine whether the following statements are true and give an explanation or counterexample. bold a. when using the shell method, the axis of the cylindrical shells is parallel to the axis of revolution. bold b. if a region is revolved about the y-axis, then the shell method must be used. bold c. if a region is revolved about the x-axis, then in principle it is possible to use the disk/washer method and integrate with respect to x or the shell method and integrate with respect to y.