David is running a unique coffee shop. He charges $25 per coffee. If a customer pays
$67 for 2 coffees, how much change should
be given back by David?

Multiply 25x 2 , which is 50 and then do 67 minus 50, which is 17. David has to give back $17 .

the law of definite proportions states samples of a compound will always contain the same proportion of elements by mass. in other words, a given compound will always contain the same elements in the same proportions by mass.the law of multiple proportions states when two elements combine with each other to form more than one compound, then the weights of one element that combine with a fixed weight of the other are in a ratio of small whole numbers.