When is subtraction always the first operation done in an expression? O Never
When it follows addition in an expression.
When it is the first operation in an expression, from left to right.
When it is in parentheses in an expression.

trapezoid

step-by-step explanation:

first i plotted all my points on a grid graph

i made sure all of them were in the correct quadrant

then i saw it was a trapezoid or a quadrilateral

answer: 12

step-by-step explanation:

because yes

54 km / hours

step-by-step explanation:

we need to convert seconds to hours

60 seconds = 1 minutes

60 minutes = 1hour

15 m         60 second   60 minutes

  * *         = 54000 meters/ hour

second     1 minute             1 hour

now we need to convert meters to km

1000 m = 1 km

54000 m       1 km

*   = 54 km / hours

hour               1000m

answer is 12345678900987654321234567890987654321

step-by-step explanation: