Doug poured 1/2 of a gallon of water into a bucket. later, he added 4/5 of a gallon more. how much water is in the bucket now?

Can someone me do math because i am having a breakdown rn because i don’t get it

Acar started driving from city a to city b, distance between which is 620 miles, at a rate of 60 mph. two hours later a truck left city b and started moving towards city a at a rate of 40 mph. what distance from city a is the point where the truck and the car will meet?

If the perimeter of the garden is 37 ft. the width is x and the length is 15 ft. what is the width of the garden in feet?