What word or abbreviation or symbol must be in the answer for area?

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

Order the measurements from the least to the greatest. 2,720 ml , 24.91 l , 0.0268 kl

Solve each quadratic equation by factoring and using the zero product property. 10x + 6 = -2x^2 -2