A positive integer is twice another. the sum of the reciprocal of the two positive integer is 3/14. Find the integers

Achemist has 200 ml of a 10% sucrose solution. she adds x ml of a 40% sucrose solution. the percent concentration, y, of the final mixture is given by the rational function: the chemist needs the concentration of the final mixture to be 30%. how many milliliters of the 40% solution should she add to the 10% solution to get this concentration?

Ihonestly have no clue if it's each or none.

Which of the following shows the graph of y=2e^x?