My weekend math homework contains 13 problems. If I solved r of them on Friday and s on Saturday, how many should I solve on Sunday? PLS HELP ME SOLVE THIS ASAP

One month, a music site observed that 60% of the people who downloaded songs from its site downloaded q sam's latest single. the equation below represents this information, where x represents the total number of people who ddownloaded songs from the site that month: x = 0.6x + 384 how many people who downloaded songs from the site that month downloaded q sam's latest single?

In a class, there are 12 girls. if the ratio of boys to girls is 5: 4 how many boys are there in the class

Parabolas y=−2x^2 and y=2x^2 +k intersect at points a and b that are in the third and the fourth quadrants respectively. find k if length of the segment ab is 5.