Raju is painting the walls and ceiling of a room with length, breadth and height of the room are 10m, 5m, 2m respectively. From each can of paint, 10m2 of area is painted. How many cans of paint will he need to paint the room?

Aman is 6 feet 3 inches tall. the top of his shadow touches a fire hydrant that is 13 feet 6 inches away. what is the angle of elevation from the base of the fire hydrant to the top of the man's head?

Expresa commuter train leaves downtown sation and travels at a average speed of 55 miles per hour towards the north side sation, which is 50miles away. thirty minutes later, express commuter train #7 leaves north side and travels at a average speed of 35miles per hour towards downtown sation. at the moment the two trains pass each other, how far(in miles) is train #12 from the downtown sation and how long(in minutes) has the #12 train been traveling

Another type of subtraction equation is 16-b=7. explain how you would sole this equation then solve it.