The piston engine uses the to convert the reciprocating motion of the piston into rotary motion.

Which of the following methods could be considered a “best practice” in terms of informing respondents how their answers to an on-line survey about personal information will be protected? respondents are informed that investigators will try to keep their participation confidential; however, confidentiality cannot be assured. respondents are informed that a research assistant will transfer all the research data to a password-protected computer that is not connected to the internet, via a usb flashdrive. the computer is located in a research team member’s office. the investigator uses the informed consent process to explain her institution’s method for guaranteeing absolute confidentiality of research data. the investigator uses the informed consent process to explain how respondent data will be transmitted from the website to his encrypted database without ever recording respondents’ ip addresses, but explains that on the internet confidentiality cannot be absolutely guaranteed.

The three logical operators used to write compound conditions are "and," "or," and "not." a: true b: false

Write a method named addall that could be placed inside the hashintset class. this method accepts another hashintset as a parameter and adds all elements from that set into the current set, if they are not already present. for example, if a set s1 contains [1, 2, 3] and another set s2 contains [1, 7, 3, 9], the call of s1.addall(s2); would change s1 to store [1, 2, 3, 7, 9] in some order. you are allowed to call methods on your set and/or the other set. do not modify the set passed in. this method should run in o(n) time where n is the number of elements in the parameter set passed in.