Amatched string is a sequence of {, }, (, ), [, and] characters that are properly matched. for example, "{{()[]}} is a matched string, but this "{{()]}" is not, since the second is matched with a]. show how to use a stack so that, given a string of length n, you can determine if it is a matched string in o(n) time. your answer should consist in a commented pseudocode or java code.

Chloe is building a kiosk-based excel application. she wants to make some modifications to the screen elements in order to keep users from being distracted by parts of the application that are irrelevant to her application. she turns to henry for guidance as she knows he built a similar solution earlier this year. chloe has decided to hide the worksheet gridlines and the vertical scroll bar. what does henry tell her to use to do this? a) screen elements dialog boxb) display options dialog boxc) customization dialog boxd) excel options dialog box

1. which of the following statements are true about routers and routing on the internet. choose two answers. a. protocols ensure that a single path between two computers is established before sending packets over it. b. routers are hierarchical and the "root" router is responsible for communicating to sub-routers the best paths for them to route internet traffic. c. a packet traveling between two computers on the internet may be rerouted many times along the way or even lost or "dropped". d. routers act independently and route packets as they see fit.

Based on the current economic situation do you expect the employment demand for graduating engineers to increase or decrease? explain the basis for your answer. with a significant economic recovery, what do you think will happen to future enrollments in graduating engineering programs?