What is the value of the 1s in 115,093,628

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

Cuántos triángulos forman un diamante

Find the volume of the solid bounded by the plane z=0 and the paraboloid z=1-x^2 –y^2