To a programmer, a system call looks like any other call to a library procedure. is it important that a programmer know which library procedures result in system calls? under what circumstances and why?

For positive constants a and b, the force between two atoms in a molecule is given f(r) = −a r2 + b r3 , where r > 0 is the distance between the atoms. note: a and b are upper case letters. (a) find f '(r) = (b) find the critical point for f(r). r = (c) find f ''(r) = (d) find the value of r so that f ''(r) = 0.

Write a program that asks the user to enter the name of an input file. if the file does not exist, the program should prompt the user to enter the file name again. if the user types quit in any uppercase/lowercase combinations, then the program should exit without any further output.

Auniform resource locator (url) is a formatted string of text that web browsers, email applications, and other software programs use to identify a particular resource on the internet. true false