A train travels at a constant 3.5 m/s with a thurst force of 300 N. If the train has a weight of 14,000 Newtons, what is the train's normal force? Ignore friction.
a. 86 kg
b. 300 N
c. 539 N
d. 704 N
URGENT I WILL GIVE BRAINLEST OR WHATEVER PLEASE HELP IM TAKING A TEST

In raising a 6200-n piano with a pulley system, the movers note that, for every 2.2 m of rope pulled down, the piano rises 0.12 m . ideally, find the force required to lift the piano.

Two point charges are on the y axis. a 3.90-µc charge is located at y = 1.25 cm, and a -2.4-µc charge is located at y = −1.80 cm. (a) find the total electric potential at the origin. v (b) find the total electric potential at the point whose coordinates are (1.50 cm, 0). v

An architect plans to use solar energy to heat the next house he designs. what principle of absorption and infrared energy can be applied to the design of the new house? how could she apply to those principals?