2.77×10^7/3×10^4 in scientific notation

What is the equation of the graph that represents f(x)=x^4 stretched vertically by 2 and shifted up 3 spaces

Ametalworker has a metal alloy that is 30? % copper and another alloy that is 55? % copper. how many kilograms of each alloy should the metalworker combine to create 90 kg of a 50? % copper? alloy?

Which is equivalent to 10/12? options: 10/18 5/6 3/12 9/11