Nora orders a bowl of Tom Yam soup at a restaurant which offers a 15% discount. The marked price of the Tom Yam soup is $6.90. Given that there is a service
charge of 10% and CST is at 7%, find the total amount of money she has to pay.

plz answer this question
i cannot understand it!

Omar is going on a road trip! the car rental company offers him two types of cars. each car has a fixed price, but he also needs to consider the cost of fuel. the first car costs $90 to rent, and because of its fuel consumption rate, there's an additional cost of s0.50 per kilometer driven.

17 in long 1.3 ft wide and 8in high what is the volume

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15