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.

Which number on the image above correctly indicates the name of a folder in this url? a.1b.2c.3d.4

Which of the following is a way that advancements in technology improve humans' ability to measure air quality and protect human health? a. air quality data gathered by new instruments can be used to reduce exposure to pollutants. b. new technologies enable natural and human-made pollution sources to be located and monitored. c. air quality data gathered by new instruments can be used to predict trends in pollution over time. d. new technologies allow governments to make informed decisions about the regulation of pollution. (choose more than one)

If you want to delete an entire word at a time, which key should you press along with the backspace or delete key?