Kaya rented a limo their one time charge was for $70 plus an hourly rate of $40. The total for her friend was also $600 for the night, how many hours (h) did kayas friend rent the limo for?

Abari owns 100 shares of stock a and 45 shares of stock b. for the past month, his stocks have been fluctuating inversely. stock a decreased by m cents per share and stock b increased by n cents per share. which equation can be used to find the total change in value of jabari's shares per month?