A train rolls to a stop along a horizontal track without the conductor applying the brakes. What answer choice BEST
explains why this occurred?
A)
The train ran out of momentum.
The opposing force of friction stopped the train.
The natural state of the train is not to be in motion.
D)
The force of gravity slowed the train until it stopped.

Google it that might work

B. because the 7 represents "seven times", x represents "a number", 12 represents "plus twelve", and -4 represents "minus four"

First step is to get rid of the square root. remember that a square root is the same as raising to the (1/2) power. see below: multiply exponents per exponent rules to get: remember you subtract exponents from the denominator and add exponents in the numerator so: simplify further: so a is the correct choice. if you don't understand this google exponent rules and it will you understand. look at the image results.