PLEASE HELP ME WHICH 2 DETAILS FROM THE TEXT BEST SUPPORTS THE ANSWER TO PART A 15 POINTS PL

Which two statements are true about a system? 1. a system is a group of objects analyzed as one unit. 2. energy that moves across system boundaries is conserved. 3. there’s only one way to define the boundaries of a system. 4. all systems are made by humans.

Late at night some traffic signals change patterns and become ?

Vera is on her school's track and field team. in a practice long-jump competition against her teammates, she gets 5 points for landing over the farther line. she gets a total of 7 jumps and lands x times over the farther line and the rest of the times over the closer line. which of the following functions represents vera's total score? a. f(x)=10x b. f(x)=5x+35 c. f(x)=10x+5 d. f(x)=70-5x