D = distance between the cars at the start of time = 680 km
v₁ = speed of one car
v₂ = speed of other car = v₁ - 10
t = time taken to meet = 4 h
distance traveled by one car in time "t" + distance traveled by other car in time "t" = D
v₁ t + v₂ t = D
(v₁ + v₂) t = D
inserting the values
(v₁ + v₁ - 10) (4) = 680
v₁ = 90 km/h
rate of slower car is given as
v₂ = v₁ - 10
v₂ = 90 - 10 = 80 km/h
Answer:
Wavelength, 
Explanation:
It is given that,
Speed of radio waves is 
Frequency of radio waves is f = 101,700,000 Hz
We need to find the wavelength of WFNX’s radio waves. The relation between wavelength, frequency and speed of a wave is given by :

is wavelength

So, the wavelength of WFNX’s radio waves is 2.94 m.
Amalgamating is the coating of zinc plate with mercury.
Answer:
ACTION REACTION FORCES
Explanation:
When there is an action frce there will be a reaction force