Please help explain this calculator code.

var calculator = {
sum: 0,
add: function(value) {
this. sum = this. sum + value;

},
clear: function() {[]
this. sum = 0;

},
equals: function() {
return this. sum;

}
}

Write a program that reads a file consisting of students’ test scores in the range 0–200. it should then determine the number of students having scores in each of the following ranges: 0–24, 25–49, 50–74, 75–99, 100–124, 125–149, 150–174, and 175–200. output the score ranges and the number of students. (run your program with the following input data: 76, 89, 150, 135, 200, 76, 12, 100, 150, 28, 178, 189, 167, 200, 175, 150, 87, 99, 129, 149, 176, 200, 87, 35, 157, 189.)

Once the data center routes to the destination server that hosts the website, what's the next step in the internet process? user’s browser renders html code from destination server into web page request goes through router/model and isp request routed to nameserver and datacenter

When early motion pictures played in movie theaters, they were often accompanied by live organ or piano music. which of the following are the most likely reasons that this happened? (select all that apply). the music was provided to distract audience members from the loud sounds made when filmstrips were changed. the music accompanied the movies because the movies were silent and audiences were used to hearing music during plays in theaters. the music usually was played before, and sometimes after the movie, as an alternative form of entertainment. the music viewers to interpret the dramatic action in the films.