The frequency will not change
ANSWER:
(a) 1036 N
(b) -1036 N
(c) 2590 N
STEP-BY-STEP EXPLANATION:
Given:
Mc = 1400 kg
Mt = 560 kg
a = 1.85 m/s^2
(a)
Force by car on trailer:

(b)

(c)
Answer:
441 [N].
Explanation:
Weight=mass*g, where mass=45; g=9,8.
Weight=45*9.8=441 [N].
It has to due with numbers so I would say the last one!
Answer:
0 Kelvin
Explanation:
Atoms in absolute temperature get approximatelly motionless since 0 Kelvin is -273 degrees Celcius. The kinetic energy of atoms/particles in matter has the possible lowest value ( almost zero), so that there is nothing colder than 0 Kelvin.