Answer:

Explanation:
Given that,
An infrared telescope is tuned to detect infrared radiation with a frequency of 4.39 THz.
We know that,
1 THz = 10¹² Hz
So,
f = 4.39 × 10¹² Hz
We need to find the wavelength of the infrared radiation.
We know that,

So, the wavelength of the infrared radiation is
.
A. Balloons can be filled with air.
C. Air has mass.
Answer:
786.6 N
Explanation:
mass of car, m = 912 kg
initial velocity of car, u = 31.5 m/s
final velocity of car, v = 24.6 m/ s
time, t = 8 s
Let a be the acceleration of the car
Use first equation of motion
v = u + a t
24.6 = 31.5 + a x 8
a = - 0.8625 m/s^2
Force, F = mass x acceleration
F = 912 x 0.8625
F = 786.6 N
Thus, the force on the car is 786.6 N.