Twin brothers, billy and bobby, can mow their grandparent's lawn together in 53 minutes. billy could mow the lawn by himself in 20 minutes less time that it would take bobby. how long would it take bobby to mow the lawn by himself?

Consider the integral: 4 0 16 − y2 − 16 − y2 4 1 x2 + y2 dz dx dy . (a) describe w. use the standard view of the x, y, and z axes. front half of a cone with a rounded top. full cone with a flat top. right half of a cone with a flat top. front half of a cone with a flat top. right half of a cone with a rounded top.

Does the problem involve permutations or? combinations? do not solve. the matching section of an exam has 4 questions and 7 possible answers. in how many different ways can a student answer the 4 ? questions, if none of the answer choices can be? repeated?

Over the last 8 nights, elyse earned the following in tips: {105, 120, 84, 95, 100, 132, 140}. if she earns $140 a night for the next four nights, which measure of center would increase more, the mean or median?